DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claim Objections
Claims 2, 8, 16, and 18-20 are objected to because of the following informalities:
In claim 2, line 1, “The device of claim 1” should read “The system of claim 1”
In claim 16, line 1, “The method of claim 4 wherein” should read “The method of claim 4, wherein”
In claim 18, line 2, “a computer coupled to or more quantum systems” should read “a computer coupled to one or more quantum systems”
In claim 20, line 1, “The system of claim 18” should read “The computer-implemented system of claim 18”
The numbering of the claims is not in accordance with 37 CFR 1.126, which requires that when new claims are presented, they must be numbered consecutively beginning with the number next following the highest numbered claims previously presented, as claim number 7 is skipped and there are two different claim number 8s. For examination purposes, the first misnumbered claim 8, reciting “The method of claim 5, wherein: the equation for the fidelity is a function of one or more parameters characterizing the coupling strength that are measured in the measurement sample, and the coupling strength is estimated using a variational method wherein the fidelity calculated from the equation is maximized by varying the one or more parameters in the equation.”, has been renumbered as claim 7.
Dependent claims 19-20 are objected based on being directly or indirectly dependent on objected claim 18.
Appropriate correction is required.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1-3 and 17 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 1 recites the limitation “the unmeasured quantum systems” in line 10. There is insufficient antecedent basis for this limitation in the claim. For examination purposes, “the unmeasured quantum systems” has been interpreted as “unmeasured quantum systems”.
Claim 3 recites the limitation “the atoms” in line 4, line 11, and line 12. There is insufficient antecedent basis for this limitation in the claim. For examination purposes, “the atoms” has been interpreted as “the neutral atoms” in reference to “neutral atoms” in line 2 of claim 3.
Claim 3 recites the limitation “the systems” in line 7 and line 8. There is insufficient antecedent basis for this limitation in the claim. For examination purposes, “the systems” has been interpreted as “the quantum systems” in reference to “quantum systems” in lines 2-3 of claim 1.
Claim 17 recites the limitation “the couplings” in line 6. There is insufficient antecedent basis for this limitation in the claim. For examination purposes, “the couplings” has been interpreted as “couplings”.
Dependent claims 2-3 are rejected based on being directly or indirectly dependent on rejected claim 1.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claim 1 is rejected under 35 U.S.C. 103 as being unpatentable over Choi et al. ("Emergent Randomness and Benchmarking from Many-Body Quantum Chaos") in view of Wunderlich et al. ("Quantum measurements and new concepts for experiments with trapped ions") and further in view of Cotler et al. ("Emergent quantum state designs from individual many-body wavefunctions").
Regarding Claim 1,
Choi et al. teaches a system for generating a pseudo random quantum state (Page 1, first-second paragraphs: "we discover that measurement results associated with small subsystems exhibit universal random statistics following chaotic quantum many-body dynamics, a phenomenon beyond the standard paradigm of quantum thermalization. We explain these observations with an ensemble of pure states, defined via correlations with the bath, that dynamically acquires a close to random distribution. Such random ensembles play an important role in quantum information science, associated with quantum supremacy tests and device verification, but typically require highly-engineered, time-dependent control for their preparation. In contrast, our approach uncovers random ensembles naturally emerging from evolution with a time-independent Hamiltonian. As an application of this emergent randomness, we develop a benchmarking protocol which estimates the many-body fidelity during generic chaotic evolution and demonstrate it using our Rydberg quantum simulator. … To reveal the emergence of random state ensembles, we employ a Rydberg analog quantum simulator, implemented with alkaline earth atoms, which provides high-fidelity preparation, evolution, and readout (Fig. 1, Ext. Data Fig. 1). The system is initialized with ten qubits in their ground state and subsequently evolved with a time-independent Hamiltonian, H, describing an array of strongly interacting qubits; Hamiltonian parameters are tuned to induce quantum thermalization to infinite temperature locally (Methods). After a variable evolution time, we perform site-resolved readout in the z-basis composed of the |0] and |1] qubit states" teaches a system for generating quantum random state ensembles (pseudo random quantum states)), comprising:
a quantum device comprising a plurality of coherently interacting quantum systems having a plurality of quantum degrees of freedom (Page 1, first-second paragraphs: "As an application of this emergent randomness, we develop a benchmarking protocol which estimates the many-body fidelity during generic chaotic evolution and demonstrate it using our Rydberg quantum simulator. … To reveal the emergence of random state ensembles, we employ a Rydberg analog quantum simulator, implemented with alkaline earth atoms, which provides high-fidelity preparation, evolution, and readout (Fig. 1, Ext. Data Fig. 1). The system is initialized with ten qubits in their ground state and subsequently evolved with a time-independent Hamiltonian, H, describing an array of strongly interacting qubits; Hamiltonian parameters are tuned to induce quantum thermalization to infinite temperature locally (Methods). After a variable evolution time, we perform site-resolved readout in the z-basis composed of the |0] and |1] qubit states" teaches a quantum simulator (quantum device) comprising a plurality of interacting atoms/qubits (coherently interacting quantum systems) having multiple qubit states (quantum degrees of freedom)),
wherein the quantum systems are prepared with a fidelity in a well characterized quantum state for the multiple quantum degrees of freedom (Page 1, first-second paragraphs: "As an application of this emergent randomness, we develop a benchmarking protocol which estimates the many-body fidelity during generic chaotic evolution and demonstrate it using our Rydberg quantum simulator. … To reveal the emergence of random state ensembles, we employ a Rydberg analog quantum simulator, implemented with alkaline earth atoms, which provides high-fidelity preparation, evolution, and readout (Fig. 1, Ext. Data Fig. 1). The system is initialized with ten qubits in their ground state and subsequently evolved with a time-independent Hamiltonian, H, describing an array of strongly interacting qubits; Hamiltonian parameters are tuned to induce quantum thermalization to infinite temperature locally (Methods). After a variable evolution time, we perform site-resolved readout in the z-basis composed of the |0] and |1] qubit states" teaches that the interacting atoms/qubits (quantum systems) are prepared with high-fidelity in a pure (well-characterized) quantum state for the multiple qubit states (quantum degrees of freedom)).
Choi et al. does not appear to explicitly teach a signal source for applying one or more signals that quantum mechanically evolve the quantum state under the influence of couplings and interactions between the quantum systems and/or between the quantum systems and a source of decoherence; and a detection system for performing a measurement on a subset of the quantum systems resulting in a second quantum state of the unmeasured quantum systems, wherein the second quantum state is used as a source of pseudo random quantum states.
However, Wunderlich et al. teaches a signal source for applying one or more signals that quantum mechanically evolve the quantum state under the influence of couplings and interactions between the quantum systems and/or between the quantum systems and a source of decoherence (Page 5, third paragraph - Page 6, first paragraph: "The coherence time of the hyperfine qubit in Yb+ is long on the time scale of qubit operations and is essentially limited by the coherence time of microwave radiation used to drive the qubit transition. In addition to the ability to perform arbitrary single-qubit operations, a second fundamental type of operation is required for QIP: conditional quantum dynamics with, at least, two qubits. … Thus, it is necessary to couple external (motional) and internal degrees of freedom. Common to all experiments performed to date – related either to QIP or other research fields – that require some kind of coupling between internal and external degrees of freedom of atoms is the use of optical radiation for this purpose. … Therefore, in usual traps, driving radiation in the optical regime is necessary to couple internal and external dynamics of trapped atoms. The distance between neighboring ions δz in a linear electrodynamic ion trap is determined by the mutual Coulomb repulsion of the ions and the time averaged force exerted on the ions by the electrodynamic trapping field. Manipulation of individual ions is usually achieved by focusing electromagnetic radiation to a spot size much smaller than δz. Again, only optical radiation is useful for this purpose. In section 6.2 a new concept for ion traps is described that allows for experiments requiring individual addressing of ions and conditional dynamics with several ions even with radiation in the radio frequency (rf) or microwave (mw) regime. … Thus, individual addressing for the purpose of single qubit operations becomes possible using long-wavelength radiation. At the same time, a coupling term between internal and motional states arises even when rf or mw radiation is applied to drive qubit transitions" teaches applying an electromagnetic radiation signal (one or more signals from signal source) that drive qubit transitions between quantum states (e.g. quantum mechanically evolve the quantum state) based on (under the influence of) couplings and interactions between the atoms/qubits (quantum systems)).
Choi et al. and Wunderlich et al. are analogous to the claimed invention because they are directed towards quantum computing.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate a signal source for applying one or more signals that quantum mechanically evolve the quantum state under the influence of couplings and interactions between the quantum systems and/or between the quantum systems and a source of decoherence as taught by Wunderlich et al. to the disclosed invention of Choi et al.
One of ordinary skill in the art would have been motivated to make this modification to allow electromagnetic radiation to be used instead of laser light for coherent manipulation of a collection of ions because "The interaction with electromagnetic radiation allows for preparation and detection of quantum states, even of single ions" (Wunderlich et al. Page 2, second paragraph).
Choi et al. in view of Wunderlich et al. does not appear to explicitly teach a detection system for performing a measurement on a subset of the quantum systems resulting in a second quantum state of the unmeasured quantum systems, wherein the second quantum state is used as a source of pseudo random quantum states.
However, Cotler et al. teaches a detection system for performing a measurement on a subset of the quantum systems resulting in a second quantum state of the unmeasured quantum systems, wherein the second quantum state is used as a source of pseudo random quantum states (Fig. 1; Page 2, first paragraph: "A subsystem B of a pure many-body wavefunction |Ψ] is measured in a fixed local basis; the remaining unmeasured qubits in A are in a pure state that depends on the measurement outcome on B. b, For quantum systems consisting of qubits, the measurement on B samples random outcomes, each characterized as a bitstring zB (binary numbers in the blue/yellow arrows). Different measurement outcomes zB occur with probability p(zB) and lead to distinct quantum states |ΨA(zB)i, forming the projected ensemble E = {p(zB), |ΨA(zB)]}. Right panel: the ensemble of pure states |ΨA(zB)] (black arrows) are randomly distributed in the Hilbert space of A (black sphere), forming an approximate quantum state k-design" teaches a measurement is performed on a subsystem B (subset) of the quantum systems resulting in an unmeasured subsystem A (unmeasured quantum systems) with a pure state (second quantum state) that is used as randomly distributed approximate random states (pseudo random quantum states)).
Choi et al., Wunderlich et al., and Cotler et al. are analogous to the claimed invention because they are directed towards quantum computing.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate a detection system for performing a measurement on a subset of the quantum systems resulting in a second quantum state of the unmeasured quantum systems, wherein the second quantum state is used as a source of pseudo random quantum states as taught by Cotler et al. to the disclosed invention of Choi et al. in view of Wunderlich et al.
One of ordinary skill in the art would have been motivated to make this modification to "offer a new approach for studying quantum chaos and provide a practical method for sampling approximately uniformly random states; the latter has wide-ranging applications in quantum information science from tomography to benchmarking" (Cotler et al. Abstract).
Claims 2 and 3 are rejected under 35 U.S.C. 103 as being unpatentable over Choi et al. ("Emergent Randomness and Benchmarking from Many-Body Quantum Chaos") in view of Wunderlich et al. ("Quantum measurements and new concepts for experiments with trapped ions") in view of Cotler et al. ("Emergent quantum state designs from individual many-body wavefunctions") and further in view of Ebadi et al. ("Quantum Phases of Matter on a 256-Atom Programmable Quantum Simulator").
Regarding Claim 2,
Choi et al. in view of Wunderlich et al. and further in view of Cotler et al. teaches the device of claim 1.
In addition, Cotler et al. further teaches wherein: the subset comprises a first plurality of the quantum systems (Fig. 1; Page 2, first paragraph: "A subsystem B of a pure many-body wavefunction |Ψ] is measured in a fixed local basis; the remaining unmeasured qubits in A are in a pure state that depends on the measurement outcome on B. b, For quantum systems consisting of qubits, the measurement on B samples random outcomes, each characterized as a bitstring zB (binary numbers in the blue/yellow arrows). Different measurement outcomes zB occur with probability p(zB) and lead to distinct quantum states |ΨA(zB)i, forming the projected ensemble E = {p(zB), |ΨA(zB)]}. Right panel: the ensemble of pure states |ΨA(zB)] (black arrows) are randomly distributed in the Hilbert space of A (black sphere), forming an approximate quantum state k-design" teaches that subsystem B (subset) of the quantum systems comprises a first plurality of the quantum systems); and
the unmeasured quantum systems comprise the remaining number of the quantum systems (Fig. 1; Page 2, first paragraph: "A subsystem B of a pure many-body wavefunction |Ψ] is measured in a fixed local basis; the remaining unmeasured qubits in A are in a pure state that depends on the measurement outcome on B. b, For quantum systems consisting of qubits, the measurement on B samples random outcomes, each characterized as a bitstring zB (binary numbers in the blue/yellow arrows). Different measurement outcomes zB occur with probability p(zB) and lead to distinct quantum states |ΨA(zB)i, forming the projected ensemble E = {p(zB), |ΨA(zB)]}. Right panel: the ensemble of pure states |ΨA(zB)] (black arrows) are randomly distributed in the Hilbert space of A (black sphere), forming an approximate quantum state k-design" teaches that unmeasured subsystem A (unmeasured quantum systems) comprises the remaining number of quantum systems not included in subsystem B (the subset) of the quantum systems).
Choi et al., Wunderlich et al., and Cotler et al. are analogous to the claimed invention because they are directed towards quantum computing.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate wherein: the subset comprises a first plurality of the quantum systems; and the unmeasured quantum systems comprise the remaining number of the quantum systems as taught by Cotler et al. to the disclosed invention of Choi et al. in view of Wunderlich et al.
One of ordinary skill in the art would have been motivated to make this modification to "offer a new approach for studying quantum chaos and provide a practical method for sampling approximately uniformly random states; the latter has wide-ranging applications in quantum information science from tomography to benchmarking" (Cotler et al. Abstract).
Choi et al. in view of Wunderlich et al. and further in view of Cotler et al. does not appear to explicitly teach wherein: the quantum systems comprise neutral atoms, quantum dots, solid state defects, superconducting qubits or qudits, or trapped ions.
However, Ebadi et al. teaches wherein: the quantum systems comprise neutral atoms, quantum dots, solid state defects, superconducting qubits or qudits, or trapped ions (Page 1, first-second paragraphs: "Recent breakthroughs have demonstrated the potential of programmable quantum systems, with system sizes reaching around fifty trapped ions or superconducting qubits, for simulations and computation. … Neutral atom arrays have recently emerged as a promising platform for realizing programmable quantum systems. Based on individually trapped and detected cold atoms in optical tweezers with strong interactions between Rydberg states, atom arrays have been utilized to explore quantum dynamics in oneand two-dimensional systems, to create high-fidelity and large-scale entanglement, to perform parallel quantum logic operations, and to realize optical atomic clocks. … Here, we realize a programmable quantum simulator using arrays of up to 256 neutral atoms with tunable interactions, demonstrating several novel quantum phases and quantitatively probing the associated phase transitions" teaches that the quantum systems comprise neutral atoms, superconducting qubits, or trapped ions).
Choi et al., Wunderlich et al., Cotler et al., and Ebadi et al. are analogous to the claimed invention because they are directed towards quantum computing.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate wherein: the quantum systems comprise neutral atoms, quantum dots, solid state defects, superconducting qubits or qudits, or trapped ions as taught by Ebadi et al. to the disclosed invention of Choi et al. in view of Wunderlich et al. and further in view of Cotler et al.
One of ordinary skill in the art would have been motivated to make this modification to provide a "hardware-efficient realization of quantum algorithms" (Ebadi et al. Abstract).
Regarding Claim 3,
Choi et al. in view of Wunderlich et al. and further in view of Cotler et al. teaches the system of claim 1.
In addition, Wunderlich et al. further teaches wherein: the signals comprise coherent electromagnetic radiation configured to: initialize the systems in the first state (Page 5, third paragraph - Page 6, first paragraph: "The coherence time of the hyperfine qubit in Yb+ is long on the time scale of qubit operations and is essentially limited by the coherence time of microwave radiation used to drive the qubit transition. In addition to the ability to perform arbitrary single-qubit operations, a second fundamental type of operation is required for QIP: conditional quantum dynamics with, at least, two qubits. … Thus, it is necessary to couple external (motional) and internal degrees of freedom. Common to all experiments performed to date – related either to QIP or other research fields – that require some kind of coupling between internal and external degrees of freedom of atoms is the use of optical radiation for this purpose. … Therefore, in usual traps, driving radiation in the optical regime is necessary to couple internal and external dynamics of trapped atoms. The distance between neighboring ions δz in a linear electrodynamic ion trap is determined by the mutual Coulomb repulsion of the ions and the time averaged force exerted on the ions by the electrodynamic trapping field. Manipulation of individual ions is usually achieved by focusing electromagnetic radiation to a spot size much smaller than δz. Again, only optical radiation is useful for this purpose. In section 6.2 a new concept for ion traps is described that allows for experiments requiring individual addressing of ions and conditional dynamics with several ions even with radiation in the radio frequency (rf) or microwave (mw) regime. … Thus, individual addressing for the purpose of single qubit operations becomes possible using long-wavelength radiation. At the same time, a coupling term between internal and motional states arises even when rf or mw radiation is applied to drive qubit transitions" teaches applying a coherent electromagnetic radiation signal (one or more signals) that drive qubit transitions between quantum states (e.g. quantum mechanically evolve the quantum state) based on (under the influence of) couplings and interactions between the atoms/qubits (quantum systems), with the qubits being initialized in a first state before the transition), and
quantum mechanically evolve the systems by applying the coherent electromagnetic radiation continuously driving a transition between the first state and second state, under the influence of the coherent electromagnetic radiation driving the transition and the interactions between the atoms (Page 5, third paragraph - Page 6, first paragraph: "The coherence time of the hyperfine qubit in Yb+ is long on the time scale of qubit operations and is essentially limited by the coherence time of microwave radiation used to drive the qubit transition. In addition to the ability to perform arbitrary single-qubit operations, a second fundamental type of operation is required for QIP: conditional quantum dynamics with, at least, two qubits. … Thus, it is necessary to couple external (motional) and internal degrees of freedom. Common to all experiments performed to date – related either to QIP or other research fields – that require some kind of coupling between internal and external degrees of freedom of atoms is the use of optical radiation for this purpose. … Therefore, in usual traps, driving radiation in the optical regime is necessary to couple internal and external dynamics of trapped atoms. The distance between neighboring ions δz in a linear electrodynamic ion trap is determined by the mutual Coulomb repulsion of the ions and the time averaged force exerted on the ions by the electrodynamic trapping field. Manipulation of individual ions is usually achieved by focusing electromagnetic radiation to a spot size much smaller than δz. Again, only optical radiation is useful for this purpose. In section 6.2 a new concept for ion traps is described that allows for experiments requiring individual addressing of ions and conditional dynamics with several ions even with radiation in the radio frequency (rf) or microwave (mw) regime. … Thus, individual addressing for the purpose of single qubit operations becomes possible using long-wavelength radiation. At the same time, a coupling term between internal and motional states arises even when rf or mw radiation is applied to drive qubit transitions" teaches applying an electromagnetic radiation signal (one or more signals from signal source) that drive qubit transitions between quantum states (e.g. quantum mechanically evolve the quantum state) based on (under the influence of) couplings and interactions between the atoms/qubits (quantum systems)).
Choi et al., Wunderlich et al., and Cotler et al. are analogous to the claimed invention because they are directed towards quantum computing.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate wherein: the signals comprise coherent electromagnetic radiation configured to: initialize the systems in the first state, and quantum mechanically evolve the systems by applying the coherent electromagnetic radiation continuously driving a transition between the first state and second state, under the influence of the coherent electromagnetic radiation driving the transition and the interactions between the atoms as taught by Wunderlich et al. to the disclosed invention of Choi et al. in view of Cotler et al.
One of ordinary skill in the art would have been motivated to make this modification to allow electromagnetic radiation to be used instead of laser light for coherent manipulation of a collection of ions because "The interaction with electromagnetic radiation allows for preparation and detection of quantum states, even of single ions" (Wunderlich et al. Page 2, second paragraph).
Choi et al. in view of Wunderlich et al. and further in view of Cotler et al. does not appear to explicitly teach wherein: the quantum device comprises an array of neutral atoms trapped in trapping potentials; the quantum systems each comprise one of the atoms comprising a first state and a second state; the interactions comprise van der Waals interactions between the atoms; and the degrees of freedom comprise the first state and the second state.
However, Ebadi et al. teaches wherein: the quantum device comprises an array of neutral atoms trapped in trapping potentials (Page 1, second paragraph: "Neutral atom arrays have recently emerged as a promising platform for realizing programmable quantum systems. Based on individually trapped and detected cold atoms in optical tweezers with strong interactions between Rydberg states, atom arrays have been utilized to explore quantum dynamics in oneand two-dimensional systems, to create high-fidelity and large-scale entanglement, to perform parallel quantum logic operations, and to realize optical atomic clocks. … Here, we realize a programmable quantum simulator using arrays of up to 256 neutral atoms with tunable interactions, demonstrating several novel quantum phases and quantitatively probing the associated phase transitions" teaches that the quantum simulator (quantum device) comprises an array of neutral atoms with trapped atoms (trapped in trapping potentials));
the quantum systems each comprise one of the atoms comprising a first state and a second state (Page 1, last paragraph: "Qubits are encoded in the electronic ground state |g] and the highly-excited n = 70 Rydberg state |r] of each atom" teaches that qubits (quantum systems) comprise atoms with a ground state (first state) and a Rydberg state (second state));
the interactions comprise van der Waals interactions between the atoms (Page 2, second paragraph: "The resulting many-body dynamics U(t) are governed by a combination of the laser excitation and long-range van der Waals interactions between Rydberg states" teaches that the interactions comprise van der Waals interactions between the Rydberg states of the atoms); and
the degrees of freedom comprise the first state and the second state (Page 1, last paragraph: "Qubits are encoded in the electronic ground state |g] and the highly-excited n = 70 Rydberg state |r] of each atom " teaches that qubits (quantum systems) comprise atoms with a ground state (first state) and a Rydberg state (second state) (e.g. the first state and second state are part of the degrees of freedom)).
Choi et al., Wunderlich et al., Cotler et al., and Ebadi et al. are analogous to the claimed invention because they are directed towards quantum computing.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate wherein: the quantum device comprises an array of neutral atoms trapped in trapping potentials; the quantum systems each comprise one of the atoms comprising a first state and a second state; the interactions comprise van der Waals interactions between the atoms; and the degrees of freedom comprise the first state and the second state as taught by Ebadi et al. to the disclosed invention of Choi et al. in view of Wunderlich et al. and further in view of Cotler et al.
One of ordinary skill in the art would have been motivated to make this modification to provide a "hardware-efficient realization of quantum algorithms" (Ebadi et al. Abstract).
Claims 4-8 and 18-20 are rejected under 35 U.S.C. 103 as being unpatentable over Sete et al. (US 2019/0007051 A1) in view of Choi et al. ("Emergent Randomness and Benchmarking from Many-Body Quantum Chaos").
Regarding Claim 4,
Sete et al. teaches a computer implemented method to verify a quantum device (Fig. 28; [0284]-[0286]: "FIG. 28 is a flowchart showing an example process 2800 for determining gate parameters for a parametrically-activated quantum logic gate. The example process 2800 can be used, for example, to … manage parametrically activated quantum logic gates for a physical quantum processor circuit. … The quantum processor circuit can be a superconducting circuit that includes many circuit devices. The circuit devices may include, for example, qubit devices … In some implementations, one or more operations in the example process 2800 can be performed by a computer system" teaches a computer-implemented process for a quantum logic gate (quantum device). Fig. 28; [0309]: "At 2816, benchmarking is performed. In some implementations, measurements such as quantum state and process tomography of entangled states (e.g. GHZ) or entangling processes are performed, and verification routines such as randomized benchmarking or gate set tomography to benchmark the fidelity and performance of the parametrically activated quantum logic gate" teaches that the process includes verification of the quantum device), comprising:
verifying at least one of a coupling strength between the quantum systems and/or between a source of decoherence and the quantum systems, or a fidelity of the quantum state (Fig. 13; [0149]-[0150]: "the simulation performed at 1305 uses a model of a quantum processor circuit to compute certain parameters that would be obtained from measuring a physical realization the quantum processor circuit. For example, the simulation may compute … a coupling strength between qubit devices, or other parameters. In some cases, the computed parameters correspond to measurements that could be obtained during a bring-up procedure or hardware test that measures, detects, diagnoses or evaluates aspects of a quantum processor circuit, its components or subsystems … In some cases, the simulations performed at 1305 indicate a quality measure (e.g., quantum process fidelity or quantum state fidelity) for simulated execution of quantum logic gates" teaches that the quantum systems are simulated (measured) and used to determine a coupling strength between qubit devices and a quantum state fidelity. Fig. 28; [0309]: "At 2816, benchmarking is performed. In some implementations, measurements such as quantum state and process tomography of entangled states (e.g. GHZ) or entangling processes are performed, and verification routines such as randomized benchmarking or gate set tomography to benchmark the fidelity and performance of the parametrically activated quantum logic gate" teaches that verification is performed for computed benchmarks (e.g. coupling strength) and for the fidelity of quantum state).
Sete et al. does not appear to explicitly teaches obtaining a quantum device comprising one or more quantum systems each having a quantum state for multiple quantum degrees of freedom; and wherein the verifying comprises comparing measurement samples of an evolved quantum state of the quantum systems, against expected behavior with time evolution obtained using a classical computer, to estimate at least one of the fidelity or the coupling strength.
However, Choi et al. teaches obtaining a quantum device comprising one or more quantum systems each having a quantum state for multiple quantum degrees of freedom (Page 1, first-second paragraphs: "As an application of this emergent randomness, we develop a benchmarking protocol which estimates the many-body fidelity during generic chaotic evolution and demonstrate it using our Rydberg quantum simulator. … To reveal the emergence of random state ensembles, we employ a Rydberg analog quantum simulator, implemented with alkaline earth atoms, which provides high-fidelity preparation, evolution, and readout (Fig. 1, Ext. Data Fig. 1). The system is initialized with ten qubits in their ground state and subsequently evolved with a time-independent Hamiltonian, H, describing an array of strongly interacting qubits; Hamiltonian parameters are tuned to induce quantum thermalization to infinite temperature locally (Methods). After a variable evolution time, we perform site-resolved readout in the z-basis composed of the |0] and |1] qubit states" teaches a quantum simulator (quantum device) comprising a plurality of interacting atoms/qubits (quantum systems) having multiple qubit states (quantum degrees of freedom)); and
wherein the verifying comprises comparing measurement samples of an evolved quantum state of the quantum systems, against expected behavior with time evolution obtained using a classical computer, to estimate at least one of the fidelity or the coupling strength (Equation 2; Page 4, first paragraph: "We can see this intuitively in the loss of correlations between target and experimental conditional probabilities as the effects of noise and imperfections accumulate over time, as shown in Fig. 4b. Formally, this loss of correlations can be used to find a fidelity estimator
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that approximates the true fidelity, Fc(t) ≈ F(t), where p(z) = [z|ρ(t)|z] and p0(z) = |[z|ψ(t)]|2 are the experimental and theoretical probabilities of observing a global bitstring z, respectively (Methods). We emphasize that Fc can be efficiently estimated without fully reconstructing the global probability distributions" teaches comparing measurement samples of the evolved quantum state (p(z)) against expected behavior with time evolution (p0(z)) by using an equation to estimate the fidelity. Fig. 4e; Page 4, last paragraph: "we can systematically vary the Hamiltonian implemented in simulation and monitor the resulting Fc to find the maximum likely Hamiltonian parameters actually realized by experiment … To capture this effect in a single quantity we plot normalized, time-integrated Fc as a function of the various Rydberg Hamiltonian parameters in Fig. 4e. For each parameter only a single sharp maximum emerges, showing good agreement with our precalibrated values, up to error bars coming from typical variations in the control parameters" teaches that the equation for the fidelity (Fc) is a function of one or more parameters measured from the experimental state (in the measurement sample), with the parameters being varied. Fig. 4e: "e, Normalized, time-integrated Fc as a function of Rabi frequency, Ω, detuning, ∆, and the interaction coefficient, C6, in the Rydberg model (Methods); these quantities are maximized only when the correct Hamiltonian parameters are assumed" teaches that the one or more parameters used for the fidelity includes the interaction coefficient C6 (coupling strength), wherein the fidelity (Fc) is maximized by varying the interaction coefficient C6 (coupling strength), meaning that the interaction coefficient C6 (coupling strength) is the value that maximizes the fidelity).
Sete et al. and Choi et al. are analogous to the claimed invention because they are directed towards quantum computing.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate obtaining a quantum device comprising one or more quantum systems each having a quantum state for multiple quantum degrees of freedom; and wherein the verifying comprises comparing measurement samples of an evolved quantum state of the quantum systems, against expected behavior with time evolution obtained using a classical computer, to estimate at least one of the fidelity or the coupling strength as taught by Choi et al. to the disclosed invention of Sete et al.
One of ordinary skill in the art would have been motivated to make this modification to provide "much shorter evolution times and with reduced experimental complexity compared to existing approaches" (Choi et al. Page 5, Col. 2, first paragraph).
Regarding Claim 5,
Sete et al. in view of Choi et al. teaches the method of claim 4.
In addition, Choi et al. further teaches wherein the comparing is performed using an equation for the fidelity (Equation 2; Page 4, first paragraph: "We can see this intuitively in the loss of correlations between target and experimental conditional probabilities as the effects of noise and imperfections accumulate over time, as shown in Fig. 4b. Formally, this loss of correlations can be used to find a fidelity estimator
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that approximates the true fidelity, Fc(t) ≈ F(t), where p(z) = [z|ρ(t)|z] and p0(z) = |[z|ψ(t)]|2 are the experimental and theoretical probabilities of observing a global bitstring z, respectively (Methods). We emphasize that Fc can be efficiently estimated without fully reconstructing the global probability distributions" teaches an equation for the fidelity to compare measurement samples).
Sete et al. and Choi et al. are analogous to the claimed invention because they are directed towards quantum computing.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate wherein the comparing is performed using an equation for the fidelity as taught by Choi et al. to the disclosed invention of Sete et al.
One of ordinary skill in the art would have been motivated to make this modification to provide "much shorter evolution times and with reduced experimental complexity compared to existing approaches" (Choi et al. Page 5, Col. 2, first paragraph).
Regarding Claim 6,
Sete et al. in view of Choi et al. teaches the method of claim 5.
In addition, Choi et al. further teaches wherein the equation is:
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where p(z) is the probability of the degree of freedom z from a calculation, q(z) is the probability from the measurement, and pd(z) is the time-averaged probability from the calculation (Equation 2; Page 4, first paragraph: "We can see this intuitively in the loss of correlations between target and experimental conditional probabilities as the effects of noise and imperfections accumulate over time, as shown in Fig. 4b. Formally, this loss of correlations can be used to find a fidelity estimator
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that approximates the true fidelity, Fc(t) ≈ F(t), where p(z) = [z|ρ(t)|z] and p0(z) = |[z|ψ(t)]|2 are the experimental and theoretical probabilities of observing a global bitstring z, respectively (Methods). We emphasize that Fc can be efficiently estimated without fully reconstructing the global probability distributions" teaches the first equation for the fidelity, wherein p0(z) (corresponds to p(z) in claimed equation) is the theoretical probability of the qubit state bitstring z (probability of the degree of freedom z), and p(z) (corresponds to q(z) in claimed equation) is the experimental probability (probability from the measurement)).
Sete et al. and Choi et al. are analogous to the claimed invention because they are directed towards quantum computing.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate wherein the equation is:
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where p(z) is the probability of the degree of freedom z from a calculation, q(z) is the probability from the measurement, and pd(z) is the time-averaged probability from the calculation as taught by Choi et al. to the disclosed invention of Sete et al.
One of ordinary skill in the art would have been motivated to make this modification to provide "much shorter evolution times and with reduced experimental complexity compared to existing approaches" (Choi et al. Page 5, Col. 2, first paragraph).
Regarding Claim 7,
Sete et al. in view of Choi et al. teaches the method of claim 5.
In addition, Choi et al. further teaches wherein: the equation for the fidelity is a function of one or more parameters characterizing the coupling strength that are measured in the measurement sample (Fig. 4e; Page 4, last paragraph: "we can systematically vary the Hamiltonian implemented in simulation and monitor the resulting Fc to find the maximum likely Hamiltonian parameters actually realized by experiment … To capture this effect in a single quantity we plot normalized, time-integrated Fc as a function of the various Rydberg Hamiltonian parameters in Fig. 4e. For each parameter only a single sharp maximum emerges, showing good agreement with our precalibrated values, up to error bars coming from typical variations in the control parameters" teaches that the equation for the fidelity (Fc) is a function of one or more parameters measured from the experimental state (in the measurement sample). Fig. 4e: "e, Normalized, time-integrated Fc as a function of Rabi frequency, Ω, detuning, ∆, and the interaction coefficient, C6, in the Rydberg model (Methods); these quantities are maximized only when the correct Hamiltonian parameters are assumed" teaches that the one or more parameters used for the fidelity includes the interaction coefficient C6 (coupling strength)), and
the coupling strength is estimated using a variational method wherein the fidelity calculated from the equation is maximized by varying the one or more parameters in the equation (Fig. 4e; Page 4, last paragraph: "we can systematically vary the Hamiltonian implemented in simulation and monitor the resulting Fc to find the maximum likely Hamiltonian parameters actually realized by experiment … To capture this effect in a single quantity we plot normalized, time-integrated Fc as a function of the various Rydberg Hamiltonian parameters in Fig. 4e. For each parameter only a single sharp maximum emerges, showing good agreement with our precalibrated values, up to error bars coming from typical variations in the control parameters" teaches that the equation for the fidelity (Fc) is a function of one or more parameters measured from the experimental state (in the measurement sample), with the parameters being varied. Fig. 4e: "e, Normalized, time-integrated Fc as a function of Rabi frequency, Ω, detuning, ∆, and the interaction coefficient, C6, in the Rydberg model (Methods); these quantities are maximized only when the correct Hamiltonian parameters are assumed" teaches that the one or more parameters used for the fidelity includes the interaction coefficient C6 (coupling strength), wherein the fidelity (Fc) is maximized by varying the interaction coefficient C6 (coupling strength), meaning that the interaction coefficient C6 (coupling strength) is the value that maximizes the fidelity).
Sete et al. and Choi et al. are analogous to the claimed invention because they are directed towards quantum computing.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate wherein: the equation for the fidelity is a function of one or more parameters characterizing the coupling strength that are measured in the measurement sample, and the coupling strength is estimated using a variational method wherein the fidelity calculated from the equation is maximized by varying the one or more parameters in the equation. as taught by Choi et al. to the disclosed invention of Sete et al.
One of ordinary skill in the art would have been motivated to make this modification to provide "much shorter evolution times and with reduced experimental complexity compared to existing approaches" (Choi et al. Page 5, Col. 2, first paragraph).
Regarding Claim 8,
Sete et al. in view of Choi et al. teaches the method of claim 5.
In addition, Choi et al. further teaches wherein the equation for the fidelity is a function of the measurement samples and the estimate is obtained by calculating the fidelity from the equation (Equation 2; Page 4, first paragraph: "We can see this intuitively in the loss of correlations between target and experimental conditional probabilities as the effects of noise and imperfections accumulate over time, as shown in Fig. 4b. Formally, this loss of correlations can be used to find a fidelity estimator
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that approximates the true fidelity, Fc(t) ≈ F(t), where p(z) = [z|ρ(t)|z] and p0(z) = |[z|ψ(t)]|2 are the experimental and theoretical probabilities of observing a global bitstring z, respectively (Methods). We emphasize that Fc can be efficiently estimated without fully reconstructing the global probability distributions" teaches estimating the fidelity using an equation that is a function of the measurement samples of the evolved quantum state (experimental probability p(z))).
Sete et al. and Choi et al. are analogous to the claimed invention because they are directed towards quantum computing.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate wherein the equation for the fidelity is a function of the measurement samples and the estimate is obtained by calculating the fidelity from the equation as taught by Choi et al. to the disclosed invention of Sete et al.
One of ordinary skill in the art would have been motivated to make this modification to provide "much shorter evolution times and with reduced experimental complexity compared to existing approaches" (Choi et al. Page 5, Col. 2, first paragraph).
Regarding Claim 18,
Sete et al. teaches a computer implemented system for verifying a quantum device (Fig. 1; Fig. 28; [0284]-[0286]: "FIG. 28 is a flowchart showing an example process 2800 for determining gate parameters for a parametrically-activated quantum logic gate. The example process 2800 can be used, for example, to … manage parametrically activated quantum logic gates for a physical quantum processor circuit. … The quantum processor circuit can be a superconducting circuit that includes many circuit devices. The circuit devices may include, for example, qubit devices … In some implementations, one or more operations in the example process 2800 can be performed by a computer" teaches a computer-implemented process for a quantum logic gate (quantum device) that can be implemented by the quantum computer system of Fig. 1. Fig. 28; [0309]: "At 2816, benchmarking is performed. In some implementations, measurements such as quantum state and process tomography of entangled states (e.g. GHZ) or entangling processes are performed, and verification routines such as randomized benchmarking or gate set tomography to benchmark the fidelity and performance of the parametrically activated quantum logic gate" teaches that the process includes verification of the quantum device), comprising:
wherein: the computer comprises one or more processors; one or more memories; and an application stored in the one or more memories ([0286]: "In some implementations, one or more operations in the example process 2800 can be performed by a computer system for instance, by a digital computer system having one or more digital processors (e.g., a microprocessor or other data processing apparatus) that execute instructions (e.g., instructions stored in a digital memory or other computer-readable medium) to perform the process 2800, or by another type of digital, quantum or hybrid computer system. As an example, in some cases the quantum processor circuit can be deployed as the quantum processor 102 shown in FIG. 1, and operations in the process 2800 shown in FIG. 28 can be controlled, executed or initiated by one or more components of the control system 110 shown in FIG. 1" teaches that the computer comprises one or more processors, one or more memories, and instructions (application) stored in the one or more memories to perform the processes described in the specification (e.g. quantum device verification)), and
the application executed by the one or more processors verifies at least one of: a coupling strength between the quantum systems and/or between a source of decoherence and the quantum systems, or a fidelity of the quantum state of interest (Fig. 13; [0149]-[0150]: "the simulation performed at 1305 uses a model of a quantum processor circuit to compute certain parameters that would be obtained from measuring a physical realization the quantum processor circuit. For example, the simulation may compute … a coupling strength between qubit devices, or other parameters. In some cases, the computed parameters correspond to measurements that could be obtained during a bring-up procedure or hardware test that measures, detects, diagnoses or evaluates aspects of a quantum processor circuit, its components or subsystems … In some cases, the simulations performed at 1305 indicate a quality measure (e.g., quantum process fidelity or quantum state fidelity) for simulated execution of quantum logic gates" teaches that the quantum systems are simulated (measured) and used to determine a coupling strength between qubit devices and a quantum state fidelity. Fig. 28; [0309]: "At 2816, benchmarking is performed. In some implementations, measurements such as quantum state and process tomography of entangled states (e.g. GHZ) or entangling processes are performed, and verification routines such as randomized benchmarking or gate set tomography to benchmark the fidelity and performance of the parametrically activated quantum logic gate" teaches that verification is performed for computed benchmarks (e.g. coupling strength) and for the fidelity of quantum state).
Sete et al. does not appear to explicitly teaches a computer coupled to or more quantum systems each having a quantum state for multiple quantum degrees of freedom, and verifies … by comparing measurement samples of an evolved quantum state of the quantum systems, against expected behavior with time evolution determined by the computer, to estimate at least one of the fidelity or the coupling strength.
However, Choi et al. teaches a computer coupled to or more quantum systems each having a quantum state for multiple quantum degrees of freedom (Page 1, first-second paragraphs: "As an application of this emergent randomness, we develop a benchmarking protocol which estimates the many-body fidelity during generic chaotic evolution and demonstrate it using our Rydberg quantum simulator. … To reveal the emergence of random state ensembles, we employ a Rydberg analog quantum simulator, implemented with alkaline earth atoms, which provides high-fidelity preparation, evolution, and readout (Fig. 1, Ext. Data Fig. 1). The system is initialized with ten qubits in their ground state and subsequently evolved with a time-independent Hamiltonian, H, describing an array of strongly interacting qubits; Hamiltonian parameters are tuned to induce quantum thermalization to infinite temperature locally (Methods). After a variable evolution time, we perform site-resolved readout in the z-basis composed of the |0] and |1] qubit states" teaches a quantum simulator (computer) comprising a plurality of interacting atoms/qubits (quantum systems) having multiple qubit states (quantum degrees of freedom)), and
verifies … by comparing measurement samples of an evolved quantum state of the quantum systems, against expected behavior with time evolution determined by the computer, to estimate at least one of the fidelity or the coupling strength (Equation 2; Page 4, first paragraph: "We can see this intuitively in the loss of correlations between target and experimental conditional probabilities as the effects of noise and imperfections accumulate over time, as shown in Fig. 4b. Formally, this loss of correlations can be used to find a fidelity estimator
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that approximates the true fidelity, Fc(t) ≈ F(t), where p(z) = [z|ρ(t)|z] and p0(z) = |[z|ψ(t)]|2 are the experimental and theoretical probabilities of observing a global bitstring z, respectively (Methods). We emphasize that Fc can be efficiently estimated without fully reconstructing the global probability distributions" teaches comparing measurement samples of the evolved quantum state (p(z)) against expected behavior with time evolution (p0(z)) by using an equation to estimate the fidelity. Fig. 4e; Page 4, last paragraph: "we can systematically vary the Hamiltonian implemented in simulation and monitor the resulting Fc to find the maximum likely Hamiltonian parameters actually realized by experiment … To capture this effect in a single quantity we plot normalized, time-integrated Fc as a function of the various Rydberg Hamiltonian parameters in Fig. 4e. For each parameter only a single sharp maximum emerges, showing good agreement with our precalibrated values, up to error bars coming from typical variations in the control parameters" teaches that the equation for the fidelity (Fc) is a function of one or more parameters measured from the experimental state (in the measurement sample), with the parameters being varied. Fig. 4e: "e, Normalized, time-integrated Fc as a function of Rabi frequency, Ω, detuning, ∆, and the interaction coefficient, C6, in the Rydberg model (Methods); these quantities are maximized only when the correct Hamiltonian parameters are assumed" teaches that the one or more parameters used for the fidelity includes the interaction coefficient C6 (coupling strength), wherein the fidelity (Fc) is maximized by varying the interaction coefficient C6 (coupling strength), meaning that the interaction coefficient C6 (coupling strength) is the value that maximizes the fidelity).
Sete et al. and Choi et al. are analogous to the claimed invention because they are directed towards quantum computing.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate a computer coupled to or more quantum systems each having a quantum state for multiple quantum degrees of freedom, and verifies … by comparing measurement samples of an evolved quantum state of the quantum systems, against expected behavior with time evolution determined by the computer, to estimate at least one of the fidelity or the coupling strength as taught by Choi et al. to the disclosed invention of Sete et al.
One of ordinary skill in the art would have been motivated to make this modification to provide "much shorter evolution times and with reduced experimental complexity compared to existing approaches" (Choi et al. Page 5, Col. 2, first paragraph).
Regarding Claim 19,
Sete et al. in view of Choi et al. teaches the computer-implemented system of claim 18.
In addition, Choi et al. further teaches wherein the application estimates the fidelity or the coupling strength by solving an equation for the fidelity (Equation 2; Page 4, first paragraph: "We can see this intuitively in the loss of correlations between target and experimental conditional probabilities as the effects of noise and imperfections accumulate over time, as shown in Fig. 4b. Formally, this loss of correlations can be used to find a fidelity estimator
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that approximates the true fidelity, Fc(t) ≈ F(t), where p(z) = [z|ρ(t)|z] and p0(z) = |[z|ψ(t)]|2 are the experimental and theoretical probabilities of observing a global bitstring z, respectively (Methods). We emphasize that Fc can be efficiently estimated without fully reconstructing the global probability distributions" teaches estimating the fidelity by solving an equation for the fidelity).
Sete et al. and Choi et al. are analogous to the claimed invention because they are directed towards quantum computing.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate wherein the application estimates the fidelity or the coupling strength by solving an equation for the fidelity as taught by Choi et al. to the disclosed invention of Sete et al.
One of ordinary skill in the art would have been motivated to make this modification to provide "much shorter evolution times and with reduced experimental complexity compared to existing approaches" (Choi et al. Page 5, Col. 2, first paragraph).
Regarding Claim 20,
Sete et al. in view of Choi et al. teaches the system of claim 18.
In addition, Choi et al. further teaches wherein the quantum device comprises a quantum simulator or quantum computer (Page 1, first-second paragraphs: "As an application of this emergent randomness, we develop a benchmarking protocol which estimates the many-body fidelity during generic chaotic evolution and demonstrate it using our Rydberg quantum simulator. … To reveal the emergence of random state ensembles, we employ a Rydberg analog quantum simulator, implemented with alkaline earth atoms, which provides high-fidelity preparation, evolution, and readout (Fig. 1, Ext. Data Fig. 1). The system is initialized with ten qubits in their ground state and subsequently evolved with a time-independent Hamiltonian, H, describing an array of strongly interacting qubits; Hamiltonian parameters are tuned to induce quantum thermalization to infinite temperature locally" teaches a quantum simulator (quantum device) for performing quantum device verification).
Sete et al. and Choi et al. are analogous to the claimed invention because they are directed towards quantum computing.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate wherein the quantum device comprises a quantum simulator or quantum computer as taught by Choi et al. to the disclosed invention of Sete et al.
One of ordinary skill in the art would have been motivated to make this modification to provide "much shorter evolution times and with reduced experimental complexity compared to existing approaches" (Choi et al. Page 5, Col. 2, first paragraph).
Claims 9 and 10 are rejected under 35 U.S.C. 103 as being unpatentable over Sete et al. (US 2019/0007051 A1) in view of Choi et al. ("Emergent Randomness and Benchmarking from Many-Body Quantum Chaos") and further in view of Liu et al. ("Redefining the Quantum Supremacy Baseline With a New Generation Sunway Supercomputer").
Regarding Claim 9,
Sete et al. in view of Choi et al. teaches the method of claim 4.
Sete et al. in view of Choi et al. does not appear to explicitly teach wherein the time evolution obtained using the classical computer uses one or more classical approximate time evolution algorithms while utilizing an approximation method to estimate the fidelity of the quantum state via an extrapolation method.
However, Liu et al. teaches wherein the time evolution obtained using the classical computer uses one or more classical approximate time evolution algorithms while utilizing an approximation method to estimate the fidelity of the quantum state via an extrapolation method (Page 1, third paragraph: "At the time of writing, a full-scale simulation of the most difficult sampling tasks performed on those quantum processors, which integrates both novelties on the classical side, namely a state of the art tensor network contraction (TNC) algorithm and a top supercomputer in the world, has not been reported. In this work, we report a highly efficient and full-scale implementation of a customized TNC algorithm on the new generation Sunway supercomputer" teaches a tensor network contraction (TNC) algorithm (classical approximate time evolution algorithm) on a classical computer for performing sampling tasks on quantum processors (time evolution obtained using classical computer) and then benchmarking XEB fidelities. Page 4, third paragraph: "The derivation of the XEB fidelities for the quantum supremacy circuits is slightly subtle since to obtain the XEB fidelities one needs to compute amplitudes of the experimentally generated bitstrings with classical computers, which is considered not possible for those circuits. … The XEB fidelities of those quantum supremacy circuits are then estimated based on two different approaches: 1) extrapolation based on component level fidelities which assumes a good suppression of the cross talks between gate operations and 2) extrapolation based on simplified variants for which a small portion of the gate operations is removed" teaches that the estimate of the XEB fidelity (fidelity of the quantum state) is approximated using via an extrapolation method).
Sete et al., Choi et al., and Liu et al. are analogous to the claimed invention because they are directed towards quantum computing.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate wherein the time evolution obtained using the classical computer uses one or more classical approximate time evolution algorithms while utilizing an approximation method to estimate the fidelity of the quantum state via an extrapolation method as taught by Liu et al. to the disclosed invention of Sete et al. in view of Choi et al.
One of ordinary skill in the art would have been motivated to make this modification "to directly compute a large number of exact amplitudes for quantum supremacy circuits with less than 14 cycles, with which we can compute the exact XEB fidelities and verify them against the estimated ones" (Liu et al. Page 4, Col. 2, first paragraph).
Regarding Claim 10,
Sete et al. in view of Choi et al. and further in view of Liu et al. teaches the method of claim 9.
In addition, Liu et al. further teaches wherein the approximate time evolution algorithms comprise one or more tensor network based algorithms, one or more path integral sampling algorithms, and/or one or more machine learning based algorithms (Page 1, third paragraph: "At the time of writing, a full-scale simulation of the most difficult sampling tasks performed on those quantum processors, which integrates both novelties on the classical side, namely a state of the art tensor network contraction (TNC) algorithm and a top supercomputer in the world, has not been reported. In this work, we report a highly efficient and full-scale implementation of a customized TNC algorithm on the new generation Sunway supercomputer" teaches a tensor network contraction (TNC) algorithm (classical approximate time evolution algorithm) on a classical computer for performing sampling tasks on quantum processors (time evolution obtained using classical computer) and then benchmarking XEB fidelities).
Sete et al., Choi et al., and Liu et al. are analogous to the claimed invention because they are directed towards quantum computing.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate wherein the approximate time evolution algorithms comprise one or more tensor network based algorithms, one or more path integral sampling algorithms, and/or one or more machine learning based algorithms as taught by Liu et al. to the disclosed invention of Sete et al. in view of Choi et al.
One of ordinary skill in the art would have been motivated to make this modification "to directly compute a large number of exact amplitudes for quantum supremacy circuits with less than 14 cycles, with which we can compute the exact XEB fidelities and verify them against the estimated ones" (Liu et al. Page 4, Col. 2, first paragraph).
Claims 11-13 are rejected under 35 U.S.C. 103 as being unpatentable over Sete et al. (US 2019/0007051 A1) in view of Choi et al. ("Emergent Randomness and Benchmarking from Many-Body Quantum Chaos") in view of Liu et al. ("Redefining the Quantum Supremacy Baseline With a New Generation Sunway Supercomputer") and further in view of Paeckel et al. ("Time-evolution methods for matrix-product states").
Regarding Claim 11,
Sete et al. in view of Choi et al. and further in view of Liu et al. teaches the method of claim 9.
Sete et al. in view of Choi et al. and further in view of Liu et al. does not appear to explicitly teach wherein a performance of the approximate time evolution algorithm is systematically tuned in order to perform the extrapolation method.
However, Paeckel et al. teaches wherein a performance of the approximate time evolution algorithm is systematically tuned in order to perform the extrapolation method (Fig. 3: "Schematic of the tensor network of a matrix-product operator (MPO). Horizontal lines denote the internal indices with bond dimension w" teaches a tensor network (approximate time evolution algorithm comprising a tensor based network algorithm) comprising bond dimensions. Section 2.6: "Operations on matrix-product states typically increase the bond dimension of the state (e.g. MPO-MPS applications or the addition of two MPS). Finding an optimal approximation to such a quantum state for a smaller bond dimension is the purpose of this section. This is of particular relevance to time-evolution methods, as entanglement generically grows during real-time evolution and time-evolved states hence per se already need a larger bond dimension than e.g. ground states. Hence finding good approximation methods is crucial. Let us consider a state |ψ] which is represented by an MPS with an initial large bond dimension m. We wish to find another state |ψ’] with smaller bond dimension m’ which approximates |ψ] well in the sense that it minimizes the Hilbert space distance |||ψ] − |ψ’]|| (13) The most direct way to proceed is to use a series of singular value decompositions to successively truncate each bond of the MPS. On each individual bond, the optimal choice is made, but this does not have to result in the globally optimal state |ψ’]. It is also possible to optimize each site tensor of |ψ’] sequentially to maximize the overlap between |ψ] and |ψ’]. Multiple sweeps of this variational optimization can be done to approach the global optimum as well as possible" teaches optimizing (tuning) a bond dimension in a tensor network for time-evolution (i.e. time evolution algorithm is tuned)).
Sete et al., Choi et al., Liu et al., and Paeckel et al. are analogous to the claimed invention because they are directed towards quantum computing.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate wherein a performance of the approximate time evolution algorithm is systematically tuned in order to perform the extrapolation method as taught by Paeckel et al. to the disclosed invention of Sete et al. in view of Choi et al. and further in view of Liu et al.
One of ordinary skill in the art would have been motivated to make this modification to "combine powerful time-evolution schemes with the efficient truncation of the exponentially-large Hilbert space intrinsic to quantum many-body systems" (Paeckel et al. Section 1, first paragraph).
Regarding Claim 12,
Sete et al. in view of Choi et al. in view of Liu et al. and further in view of Paeckel et al. teaches the method of claim 11.
In addition, Paeckel et al. further teaches wherein the performance of the approximate time evolution algorithm comprising a tensor based network algorithm can be tuned by changing a bond dimension (Fig. 3: " Schematic of the tensor network of a matrix-product operator (MPO). Horizontal lines denote the internal indices with bond dimension w" teaches a tensor network (approximate time evolution algorithm comprising a tensor based network algorithm) comprising bond dimensions. Section 2.6: "Operations on matrix-product states typically increase the bond dimension of the state (e.g. MPO-MPS applications or the addition of two MPS). Finding an optimal approximation to such a quantum state for a smaller bond dimension is the purpose of this section. This is of particular relevance to time-evolution methods, as entanglement generically grows during real-time evolution and time-evolved states hence per se already need a larger bond dimension than e.g. ground states. Hence finding good approximation methods is crucial. Let us consider a state |ψ] which is represented by an MPS with an initial large bond dimension m. We wish to find another state |ψ’] with smaller bond dimension m’ which approximates |ψ] well in the sense that it minimizes the Hilbert space distance |||ψ] − |ψ’]|| (13) The most direct way to proceed is to use a series of singular value decompositions to successively truncate each bond of the MPS. On each individual bond, the optimal choice is made, but this does not have to result in the globally optimal state |ψ’]. It is also possible to optimize each site tensor of |ψ’] sequentially to maximize the overlap between |ψ] and |ψ’]. Multiple sweeps of this variational optimization can be done to approach the global optimum as well as possible" teaches optimizing (tuning) a bond dimension in a tensor network for time-evolution).
Sete et al., Choi et al., Liu et al., and Paeckel et al. are analogous to the claimed invention because they are directed towards quantum computing.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate wherein the performance of the approximate time evolution algorithm comprising a tensor based network algorithm can be tuned by changing a bond dimension as taught by Paeckel et al. to the disclosed invention of Sete et al. in view of Choi et al. and further in view of Liu et al.
One of ordinary skill in the art would have been motivated to make this modification to "combine powerful time-evolution schemes with the efficient truncation of the exponentially-large Hilbert space intrinsic to quantum many-body systems" (Paeckel et al. Section 1, first paragraph).
Regarding Claim 13,
Sete et al. in view of Choi et al. in view of Liu et al. and further in view of Paeckel et al. teaches the method of claim 11.
In addition, Choi et al. further teaches wherein the systematic tuning is at least one of short delay time extrapolation or extrapolation via classical control (Page 16, second paragraph: "if Fc is evaluated after some delay time from the error, then V (τ) becomes scrambled in the operator basis, and F can be approximately estimated. In other words, even in the case of the diagonal errors, our formula becomes valid after a finite delay time τd" teaches that the fidelity estimate can be tuned by doing a short time delay extrapolation to tune in the case of error).
Sete et al., Choi et al., Liu et al., and Paeckel et al. are analogous to the claimed invention because they are directed towards quantum computing.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate wherein the systematic tuning is at least one of short delay time extrapolation or extrapolation via classical control as taught by Choi et al. to the disclosed invention of Sete et al. in view of Liu et al. and further in view of Paeckel et al.
One of ordinary skill in the art would have been motivated to make this modification to provide "much shorter evolution times and with reduced experimental complexity compared to existing approaches" (Choi et al. Page 5, Col. 2, first paragraph).
Claims 14-16 are rejected under 35 U.S.C. 103 as being unpatentable over Sete et al. (US 2019/0007051 A1) in view of Choi et al. ("Emergent Randomness and Benchmarking from Many-Body Quantum Chaos") and further in view of Wunderlich et al. ("Quantum measurements and new concepts for experiments with trapped ions").
Regarding Claim 14,
Sete et al. in view of Choi et al. teaches the method of claim 4.
In addition, Choi et al. further teaches wherein the verifying characterizes the coupling strength by: (a) preparing the quantum state of the quantum device, wherein the quantum state is well known (Fig. 1a; Page 1, second paragraph: "To reveal the emergence of random state ensembles, we employ a Rydberg analog quantum simulator, implemented with alkaline earth atoms, which provides high-fidelity preparation, evolution, and readout (Fig. 1, Ext. Data Fig. 1). The system is initialized with ten qubits in their ground state" teaches that the interacting atoms/qubits (quantum systems) are initialized (prepared) with their ground state (well-known quantum state));
(c) performing a measurement on all quantum degrees of freedom of the quantum systems resulting in a particular measurement sample of the quantum state (Fig. 1a: "a, We experimentally implement chaotic quantum many-body dynamics with a Rydberg quantum simulator, described by a time-independent Hamiltonian, H, starting from an initial product state of ten qubits (Methods). We perform site-resolved, projective measurements yielding an outcome 0 or 1 for finding each qubit in state |0] or |1], respectively" teaches a measurement is performed on the quantum states (quantum degrees of freedom) of each qubit (quantum systems) to determine measurement samples of the quantum state);
(d) repeating steps (a)-(c) to obtain a plurality of the measurement samples (Fig. 1a; Fig. 1b: "a, We experimentally implement chaotic quantum many-body dynamics with a Rydberg quantum simulator, described by a time-independent Hamiltonian, H, starting from an initial product state of ten qubits (Methods). We perform site-resolved, projective measurements yielding an outcome 0 or 1 for finding each qubit in state |0] or |1], respectively. We bipartition the system into two subsystems A and B, for which we record bitstrings zA of length LA and bitstrings zB of length LB, for the qubits in the corresponding subsystems. b, We first choose a subsystem A that consists of only a single qubit (LA = 1) and plot probabilities of finding the qubit in state |0], conditioned on specific measurement results zB in B, p(zA=0|zB). Trajectories of p(zA=0|zB) for all outcomes zB (color varying from red to blue) are shown as a function of time. We find that the different trajectories develop a significant dependence on zB at late times, exhibiting apparently chaotic behavior" teaches a measurement is performed on the quantum states (quantum degrees of freedom) of each qubit (quantum systems) to determine measurement samples of the quantum state repeatedly over time to obtain a plurality of measurements); and
(e) comparing the measurement samples against the expected behavior with the time evolution obtained using the classical computer to obtain the estimate of the coupling strength (Equation 2; Page 4, first paragraph: "We can see this intuitively in the loss of correlations between target and experimental conditional probabilities as the effects of noise and imperfections accumulate over time, as shown in Fig. 4b. Formally, this loss of correlations can be used to find a fidelity estimator
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that approximates the true fidelity, Fc(t) ≈ F(t), where p(z) = [z|ρ(t)|z] and p0(z) = |[z|ψ(t)]|2 are the experimental and theoretical probabilities of observing a global bitstring z, respectively (Methods). We emphasize that Fc can be efficiently estimated without fully reconstructing the global probability distributions" teaches comparing measurement samples of the evolved quantum state (p(z)) against expected behavior with time evolution (p0(z)) by using an equation to estimate the fidelity. Fig. 4e; Page 4, last paragraph: "we can systematically vary the Hamiltonian implemented in simulation and monitor the resulting Fc to find the maximum likely Hamiltonian parameters actually realized by experiment … To capture this effect in a single quantity we plot normalized, time-integrated Fc as a function of the various Rydberg Hamiltonian parameters in Fig. 4e. For each parameter only a single sharp maximum emerges, showing good agreement with our precalibrated values, up to error bars coming from typical variations in the control parameters" teaches that the equation for the fidelity (Fc) is a function of one or more parameters measured from the experimental state (in the measurement sample), with the parameters being varied. Fig. 4e: "e, Normalized, time-integrated Fc as a function of Rabi frequency, Ω, detuning, ∆, and the interaction coefficient, C6, in the Rydberg model (Methods); these quantities are maximized only when the correct Hamiltonian parameters are assumed" teaches that the one or more parameters used for the fidelity includes the interaction coefficient C6 (coupling strength), wherein the fidelity (Fc) is maximized by varying the interaction coefficient C6 (coupling strength), meaning that the interaction coefficient C6 (coupling strength) is the value that maximizes the fidelity).
Sete et al. and Choi et al. are analogous to the claimed invention because they are directed towards quantum computing.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate wherein the verifying characterizes the coupling strength by:(a) preparing the quantum state of the quantum device, wherein the quantum state is well known; (c) performing a measurement on all quantum degrees of freedom of the quantum systems resulting in a particular measurement sample of the quantum state; (d) repeating steps (a)-(c) to obtain a plurality of the measurement samples; and (e) comparing the measurement samples against the expected behavior with the time evolution obtained using the classical computer to obtain the estimate of the coupling strength. as taught by Choi et al. to the disclosed invention of Sete et al.
One of ordinary skill in the art would have been motivated to make this modification to provide "much shorter evolution times and with reduced experimental complexity compared to existing approaches" (Choi et al. Page 5, Col. 2, first paragraph).
Sete et al. in view of Choi et al. does not appear to explicitly teach (b) applying one or more signals to quantum mechanically evolve the well-known quantum state under an influence of couplings and interactions between the quantum systems and/or between the quantum systems and a source of noise.
However, Wunderlich et al. teaches (b) applying one or more signals to quantum mechanically evolve the well-known quantum state under an influence of couplings and interactions between the quantum systems and/or between the quantum systems and a source of noise (Page 5, third paragraph - Page 6, first paragraph: "The coherence time of the hyperfine qubit in Yb+ is long on the time scale of qubit operations and is essentially limited by the coherence time of microwave radiation used to drive the qubit transition. In addition to the ability to perform arbitrary single-qubit operations, a second fundamental type of operation is required for QIP: conditional quantum dynamics with, at least, two qubits. … Thus, it is necessary to couple external (motional) and internal degrees of freedom. Common to all experiments performed to date – related either to QIP or other research fields – that require some kind of coupling between internal and external degrees of freedom of atoms is the use of optical radiation for this purpose. … Therefore, in usual traps, driving radiation in the optical regime is necessary to couple internal and external dynamics of trapped atoms. The distance between neighboring ions δz in a linear electrodynamic ion trap is determined by the mutual Coulomb repulsion of the ions and the time averaged force exerted on the ions by the electrodynamic trapping field. Manipulation of individual ions is usually achieved by focusing electromagnetic radiation to a spot size much smaller than δz. Again, only optical radiation is useful for this purpose. In section 6.2 a new concept for ion traps is described that allows for experiments requiring individual addressing of ions and conditional dynamics with several ions even with radiation in the radio frequency (rf) or microwave (mw) regime. … Thus, individual addressing for the purpose of single qubit operations becomes possible using long-wavelength radiation. At the same time, a coupling term between internal and motional states arises even when rf or mw radiation is applied to drive qubit transitions" teaches applying an electromagnetic radiation signal (one or more signals from signal source) that drive qubit transitions between quantum states (e.g. quantum mechanically evolve the quantum state) based on (under the influence of) couplings and interactions between the atoms/qubits (quantum systems)).
Sete et al., Choi et al., and Wunderlich et al. are analogous to the claimed invention because they are directed towards quantum computing.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate (b) applying one or more signals to quantum mechanically evolve the well-known quantum state under an influence of couplings and interactions between the quantum systems and/or between the quantum systems and a source of noise as taught by Wunderlich et al. to the disclosed invention of Sete et al. in view of Choi et al.
One of ordinary skill in the art would have been motivated to make this modification to allow electromagnetic radiation to be used instead of laser light for coherent manipulation of a collection of ions because "The interaction with electromagnetic radiation allows for preparation and detection of quantum states, even of single ions" (Wunderlich et al. Page 2, second paragraph).
Regarding Claim 15,
Sete et al. in view of Choi et al. teaches the method of claim 4.
In addition, Choi et al. further teaches wherein the verifying characterizes the fidelity by:(a) preparing the quantum state with unknown fidelity (Fig. 1a: "a, We experimentally implement chaotic quantum many-body dynamics with a Rydberg quantum simulator, described by a time-independent Hamiltonian, H, starting from an initial product state of ten qubits" teaches that the qubits (quantum systems) are initialized (prepared) to an initial product state (quantum state with unknown fidelity));
(c) performing measurement on all quantum degrees of freedom of the evolved quantum state resulting in a particular measurement sample of the evolved quantum state (Fig. 1a: "a, We experimentally implement chaotic quantum many-body dynamics with a Rydberg quantum simulator, described by a time-independent Hamiltonian, H, starting from an initial product state of ten qubits (Methods). We perform site-resolved, projective measurements yielding an outcome 0 or 1 for finding each qubit in state |0] or |1], respectively" teaches a measurement is performed on the quantum states (quantum degrees of freedom) of each qubit (quantum systems) to determine measurement samples of the evolved quantum state);
(d) repeating steps (a)-(c) to obtain a plurality of the measurement samples (Fig. 1a; Fig. 1b: "a, We experimentally implement chaotic quantum many-body dynamics with a Rydberg quantum simulator, described by a time-independent Hamiltonian, H, starting from an initial product state of ten qubits (Methods). We perform site-resolved, projective measurements yielding an outcome 0 or 1 for finding each qubit in state |0] or |1], respectively. We bipartition the system into two subsystems A and B, for which we record bitstrings zA of length LA and bitstrings zB of length LB, for the qubits in the corresponding subsystems. b, We first choose a subsystem A that consists of only a single qubit (LA = 1) and plot probabilities of finding the qubit in state |0], conditioned on specific measurement results zB in B, p(zA=0|zB). Trajectories of p(zA=0|zB) for all outcomes zB (color varying from red to blue) are shown as a function of time. We find that the different trajectories develop a significant dependence on zB at late times, exhibiting apparently chaotic behavior" teaches a measurement is performed on the quantum states (quantum degrees of freedom) of each qubit (quantum systems) to determine measurement samples of the quantum state repeatedly over time to obtain a plurality of measurements); and
(e) comparing the measurement samples against the expected behavior with time evolution obtained using the classical computer to obtain the estimate of the fidelity of the quantum state (Equation 2; Page 4, first paragraph: "We can see this intuitively in the loss of correlations between target and experimental conditional probabilities as the effects of noise and imperfections accumulate over time, as shown in Fig. 4b. Formally, this loss of correlations can be used to find a fidelity estimator
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that approximates the true fidelity, Fc(t) ≈ F(t), where p(z) = [z|ρ(t)|z] and p0(z) = |[z|ψ(t)]|2 are the experimental and theoretical probabilities of observing a global bitstring z, respectively (Methods). We emphasize that Fc can be efficiently estimated without fully reconstructing the global probability distributions" teaches comparing measurement samples of the evolved quantum state (p(z)) against expected behavior with time evolution (p0(z)) by using an equation to estimate the fidelity).
Sete et al. and Choi et al. are analogous to the claimed invention because they are directed towards quantum computing.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate wherein the verifying characterizes the fidelity by:(a) preparing the quantum state with unknown fidelity; (c) performing measurement on all quantum degrees of freedom of the evolved quantum state resulting in a particular measurement sample of the evolved quantum state; (d) repeating steps (a)-(c) to obtain a plurality of the measurement samples; and (e) comparing the measurement samples against the expected behavior with time evolution obtained using the classical computer to obtain the estimate of the fidelity of the quantum state as taught by Choi et al. to the disclosed invention of Sete et al.
One of ordinary skill in the art would have been motivated to make this modification to provide "much shorter evolution times and with reduced experimental complexity compared to existing approaches" (Choi et al. Page 5, Col. 2, first paragraph).
Sete et al. in view of Choi et al. does not appear to explicitly teach (b) applying one or more signals to quantum mechanically evolve the quantum state for a well-known time duration under an influence of known couplings and interactions, to form an evolved quantum state.
However, Wunderlich et al. teaches (b) applying one or more signals to quantum mechanically evolve the quantum state for a well-known time duration under an influence of known couplings and interactions, to form an evolved quantum state (Page 5, third paragraph - Page 6, first paragraph: "The coherence time of the hyperfine qubit in Yb+ is long on the time scale of qubit operations and is essentially limited by the coherence time of microwave radiation used to drive the qubit transition. In addition to the ability to perform arbitrary single-qubit operations, a second fundamental type of operation is required for QIP: conditional quantum dynamics with, at least, two qubits. … Thus, it is necessary to couple external (motional) and internal degrees of freedom. Common to all experiments performed to date – related either to QIP or other research fields – that require some kind of coupling between internal and external degrees of freedom of atoms is the use of optical radiation for this purpose. … Therefore, in usual traps, driving radiation in the optical regime is necessary to couple internal and external dynamics of trapped atoms. The distance between neighboring ions δz in a linear electrodynamic ion trap is determined by the mutual Coulomb repulsion of the ions and the time averaged force exerted on the ions by the electrodynamic trapping field. Manipulation of individual ions is usually achieved by focusing electromagnetic radiation to a spot size much smaller than δz. Again, only optical radiation is useful for this purpose. In section 6.2 a new concept for ion traps is described that allows for experiments requiring individual addressing of ions and conditional dynamics with several ions even with radiation in the radio frequency (rf) or microwave (mw) regime. … Thus, individual addressing for the purpose of single qubit operations becomes possible using long-wavelength radiation. At the same time, a coupling term between internal and motional states arises even when rf or mw radiation is applied to drive qubit transitions" teaches applying an electromagnetic radiation signal (one or more signals from signal source) that drive qubit transitions between quantum states (e.g. quantum mechanically evolve the quantum state) based on (under the influence of) couplings and interactions between the atoms/qubits (quantum systems)).
Sete et al., Choi et al., and Wunderlich et al. are analogous to the claimed invention because they are directed towards quantum computing.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate (b) applying one or more signals to quantum mechanically evolve the quantum state for a well-known time duration under an influence of known couplings and interactions, to form an evolved quantum state as taught by Wunderlich et al. to the disclosed invention of Sete et al. in view of Choi et al.
One of ordinary skill in the art would have been motivated to make this modification to allow electromagnetic radiation to be used instead of laser light for coherent manipulation of a collection of ions because "The interaction with electromagnetic radiation allows for preparation and detection of quantum states, even of single ions" (Wunderlich et al. Page 2, second paragraph).
Regarding Claim 16,
Sete et al. in view of Choi et al. teaches the method of claim 4.
In addition, Choi et al. further teaches wherein the verifying characterizes the fidelity and the coupling strength simultaneously by: (a) preparing an initial quantum state of the quantum device, wherein the initial quantum state is initially imperfectly known with unknown fidelity (Fig. 1a: " a, We experimentally implement chaotic quantum many-body dynamics with a Rydberg quantum simulator, described by a time-independent Hamiltonian, H, starting from an initial product state of ten qubits" teaches that the qubits (quantum systems) are initialized (prepared) to an initial product state (quantum state with unknown fidelity));
(c) performing a measurement on all quantum degrees of freedom of the quantum systems resulting in a particular measurement sample of the quantum state (Fig. 1a: "a, We experimentally implement chaotic quantum many-body dynamics with a Rydberg quantum simulator, described by a time-independent Hamiltonian, H, starting from an initial product state of ten qubits (Methods). We perform site-resolved, projective measurements yielding an outcome 0 or 1 for finding each qubit in state |0] or |1], respectively" teaches a measurement is performed on the quantum states (quantum degrees of freedom) of each qubit (quantum systems) to determine measurement samples of the quantum state);
(d) repeating steps (a)-(c) to obtain a plurality of the measurement samples (Fig. 1a; Fig. 1b: "a, We experimentally implement chaotic quantum many-body dynamics with a Rydberg quantum simulator, described by a time-independent Hamiltonian, H, starting from an initial product state of ten qubits (Methods). We perform site-resolved, projective measurements yielding an outcome 0 or 1 for finding each qubit in state |0] or |1], respectively. We bipartition the system into two subsystems A and B, for which we record bitstrings zA of length LA and bitstrings zB of length LB, for the qubits in the corresponding subsystems. b, We first choose a subsystem A that consists of only a single qubit (LA = 1) and plot probabilities of finding the qubit in state |0], conditioned on specific measurement results zB in B, p(zA=0|zB). Trajectories of p(zA=0|zB) for all outcomes zB (color varying from red to blue) are shown as a function of time. We find that the different trajectories develop a significant dependence on zB at late times, exhibiting apparently chaotic behavior" teaches a measurement is performed on the quantum states (quantum degrees of freedom) of each qubit (quantum systems) to determine measurement samples of the quantum state repeatedly over time to obtain a plurality of measurements); and
(e) comparing the measurement samples against the expected behavior with the time evolution obtained using the classical computer to obtain the estimate of the coupling strength and/or the estimate of the fidelity (Equation 2; Page 4, first paragraph: "We can see this intuitively in the loss of correlations between target and experimental conditional probabilities as the effects of noise and imperfections accumulate over time, as shown in Fig. 4b. Formally, this loss of correlations can be used to find a fidelity estimator
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that approximates the true fidelity, Fc(t) ≈ F(t), where p(z) = [z|ρ(t)|z] and p0(z) = |[z|ψ(t)]|2 are the experimental and theoretical probabilities of observing a global bitstring z, respectively (Methods). We emphasize that Fc can be efficiently estimated without fully reconstructing the global probability distributions" teaches comparing measurement samples of the evolved quantum state (p(z)) against expected behavior with time evolution (p0(z)) by using an equation to estimate the fidelity. Fig. 4e; Page 4, last paragraph: "we can systematically vary the Hamiltonian implemented in simulation and monitor the resulting Fc to find the maximum likely Hamiltonian parameters actually realized by experiment … To capture this effect in a single quantity we plot normalized, time-integrated Fc as a function of the various Rydberg Hamiltonian parameters in Fig. 4e. For each parameter only a single sharp maximum emerges, showing good agreement with our precalibrated values, up to error bars coming from typical variations in the control parameters" teaches that the equation for the fidelity (Fc) is a function of one or more parameters measured from the experimental state (in the measurement sample), with the parameters being varied. Fig. 4e: "e, Normalized, time-integrated Fc as a function of Rabi frequency, Ω, detuning, ∆, and the interaction coefficient, C6, in the Rydberg model (Methods); these quantities are maximized only when the correct Hamiltonian parameters are assumed" teaches that the one or more parameters used for the fidelity includes the interaction coefficient C6 (coupling strength), wherein the fidelity (Fc) is maximized by varying the interaction coefficient C6 (coupling strength), meaning that the interaction coefficient C6 (coupling strength) is the value that maximizes the fidelity).
Sete et al. and Choi et al. are analogous to the claimed invention because they are directed towards quantum computing.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate wherein the verifying characterizes the fidelity and the coupling strength simultaneously by: (a) preparing an initial quantum state of the quantum device, wherein the initial quantum state is initially imperfectly known with unknown fidelity; (c) performing a measurement on all quantum degrees of freedom of the quantum systems resulting in a particular measurement sample of the quantum state; (d) repeating steps (a)-(c) to obtain a plurality of the measurement samples; and (e) comparing the measurement samples against the expected behavior with the time evolution obtained using the classical computer to obtain the estimate of the coupling strength and/or the estimate of the fidelity as taught by Choi et al. to the disclosed invention of Sete et al.
One of ordinary skill in the art would have been motivated to make this modification to provide "much shorter evolution times and with reduced experimental complexity compared to existing approaches" (Choi et al. Page 5, Col. 2, first paragraph).
Additionally, Sete et al. further teaches wherein: the estimate of the fidelity in step(e) is used as an input to provide knowledge of the fidelity in a next iteration of step (a) (Fig. 13: [0158]: "In some cases, the testing and measuring at 1320 includes the parameterization and execution of quantum logic gates or quantum logic algorithms. … In some cases, the testing and measuring at 1320 determine a quality measure (e.g., quantum process fidelity or quantum state fidelity) for the execution of quantum logic gates in the quantum processor circuit" teaches that the fidelity is determined (calculated) based on the measurements of the qubit devices (quantum systems). Fig. 13; [0144]: "the process 1300 proceeds in an iterative manner, for example, iteratively … measuring various parameters associated with the fabricated quantum processor circuits. In some cases, individual operations or groups of operations can be repeated multiple times, for example, in order to optimize or otherwise improve a quantum processor circuits" teaches that the measured parameters (e.g. the fidelity) are used to iteratively optimize the quantum systems (i.e. the determined fidelity is used in the next iteration)), and
the estimate of the coupling strength obtained in step (e) is an input to provide the knowledge of the coupling in step (b), so that performance of the method simultaneously estimates the fidelity of the initial quantum state and the coupling strength (Fig. 13: [0156]: "In some cases, the testing and measuring at 1320 includes characterizing (fully or partially characterize) each qubit device in the quantum processor circuit. For example, each qubit device may be characterized by measuring or otherwise determining the … coupling strength to other qubit devices, or other parameters" teaches that the coupling strength is determined (calculated) based on the measurements of the qubit devices (quantum systems). Fig. 13; [0144]: "the process 1300 proceeds in an iterative manner, for example, iteratively … measuring various parameters associated with the fabricated quantum processor circuits. In some cases, individual operations or groups of operations can be repeated multiple times, for example, in order to optimize or otherwise improve a quantum processor circuits" teaches that the measured parameters (e.g. the coupling strength) are used to iteratively optimize the quantum systems (i.e. the determined coupling strength is used in the next iteration)).
Sete et al. in view of Choi et al. does not appear to explicitly teach (b) applying one or more signals to quantum mechanically evolve the quantum state for a known time duration and under an influence of couplings and interactions between the quantum systems and/or between the quantum systems and a source of noise, wherein the couplings are initially imperfectly unknown.
However, Wunderlich et al. teaches (b) applying one or more signals to quantum mechanically evolve the quantum state for a known time duration and under an influence of couplings and interactions between the quantum systems and/or between the quantum systems and a source of noise, wherein the couplings are initially imperfectly unknown (Page 5, third paragraph - Page 6, first paragraph: "The coherence time of the hyperfine qubit in Yb+ is long on the time scale of qubit operations and is essentially limited by the coherence time of microwave radiation used to drive the qubit transition. In addition to the ability to perform arbitrary single-qubit operations, a second fundamental type of operation is required for QIP: conditional quantum dynamics with, at least, two qubits. … Thus, it is necessary to couple external (motional) and internal degrees of freedom. Common to all experiments performed to date – related either to QIP or other research fields – that require some kind of coupling between internal and external degrees of freedom of atoms is the use of optical radiation for this purpose. … Therefore, in usual traps, driving radiation in the optical regime is necessary to couple internal and external dynamics of trapped atoms. The distance between neighboring ions δz in a linear electrodynamic ion trap is determined by the mutual Coulomb repulsion of the ions and the time averaged force exerted on the ions by the electrodynamic trapping field. Manipulation of individual ions is usually achieved by focusing electromagnetic radiation to a spot size much smaller than δz. Again, only optical radiation is useful for this purpose. In section 6.2 a new concept for ion traps is described that allows for experiments requiring individual addressing of ions and conditional dynamics with several ions even with radiation in the radio frequency (rf) or microwave (mw) regime. … Thus, individual addressing for the purpose of single qubit operations becomes possible using long-wavelength radiation. At the same time, a coupling term between internal and motional states arises even when rf or mw radiation is applied to drive qubit transitions" teaches applying an electromagnetic radiation signal (one or more signals from signal source) that drive qubit transitions between quantum states (e.g. quantum mechanically evolve the quantum state) based on (under the influence of) couplings and interactions between the atoms/qubits (quantum systems)).
Sete et al., Choi et al., and Wunderlich et al. are analogous to the claimed invention because they are directed towards quantum computing.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate (b) applying one or more signals to quantum mechanically evolve the quantum state for a known time duration and under an influence of couplings and interactions between the quantum systems and/or between the quantum systems and a source of noise, wherein the couplings are initially imperfectly unknown as taught by Wunderlich et al. to the disclosed invention of Sete et al. in view of Choi et al.
One of ordinary skill in the art would have been motivated to make this modification to allow electromagnetic radiation to be used instead of laser light for coherent manipulation of a collection of ions because "The interaction with electromagnetic radiation allows for preparation and detection of quantum states, even of single ions" (Wunderlich et al. Page 2, second paragraph).
Claim 17 is rejected under 35 U.S.C. 103 as being unpatentable over Sete et al. (US 2019/0007051 A1) in view of Choi et al. ("Emergent Randomness and Benchmarking from Many-Body Quantum Chaos") in view of Ebadi et al. ("Quantum Phases of Matter on a 256-Atom Programmable Quantum Simulator") and further in view of Wunderlich et al. ("Quantum measurements and new concepts for experiments with trapped ions").
Regarding Claim 17,
Sete et al. in view of Choi et al. teaches the method of claim 4.
Sete et al. in view of Choi et al. does not appear to explicitly teach wherein: the quantum device comprises an array of neutral atoms trapped in trapping potentials and the quantum systems comprise a first state and a second state of each of the atoms, and the interactions comprise interactions between the atoms, and the couplings comprise coherent electromagnetic radiation driving a transition between the first state and the second state and the coupling strength is a function of the detuning of the coherent electromagnetic radiation from the transition.
However, Ebadi et al. teaches wherein: the quantum device comprises an array of neutral atoms trapped in trapping potentials and the quantum systems comprise a first state and a second state of each of the atoms (Page 1, second paragraph: "Neutral atom arrays have recently emerged as a promising platform for realizing programmable quantum systems. Based on individually trapped and detected cold atoms in optical tweezers with strong interactions between Rydberg states, atom arrays have been utilized to explore quantum dynamics in oneand two-dimensional systems, to create high-fidelity and large-scale entanglement, to perform parallel quantum logic operations, and to realize optical atomic clocks. … Here, we realize a programmable quantum simulator using arrays of up to 256 neutral atoms with tunable interactions, demonstrating several novel quantum phases and quantitatively probing the associated phase transitions" teaches that the quantum simulator (quantum device) comprises an array of neutral atoms with trapped atoms (trapped in trapping potentials). Page 1, last paragraph: "Qubits are encoded in the electronic ground state |g] and the highly-excited n = 70 Rydberg state |r] of each atom" teaches that qubits (quantum systems) comprise atoms with a ground state (first state) and a Rydberg state (second state)), and
the interactions comprise interactions between the atoms (Page 2, second paragraph: "The resulting many-body dynamics U(t) are governed by a combination of the laser excitation and long-range van der Waals interactions between Rydberg states" teaches that the interactions comprise van der Waals interactions between the Rydberg states of the atoms (interactions between atoms)).
Sete et al., Choi et al., and Ebadi et al. are analogous to the claimed invention because they are directed towards quantum computing.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate wherein: the quantum device comprises an array of neutral atoms trapped in trapping potentials and the quantum systems comprise a first state and a second state of each of the atoms, and the interactions comprise interactions between the atoms as taught by Ebadi et al. to the disclosed invention of Sete et al. in view of Choi et al.
One of ordinary skill in the art would have been motivated to make this modification to provide a "hardware-efficient realization of quantum algorithms" (Ebadi et al. Abstract).
Sete et al. in view of Choi et al. and further in view of Ebadi et al. does not appear to explicitly teach the couplings comprise coherent electromagnetic radiation driving a transition between the first state and the second state and the coupling strength is a function of the detuning of the coherent electromagnetic radiation from the transition.
However, Wunderlich et al. teaches the couplings comprise coherent electromagnetic radiation driving a transition between the first state and the second state and the coupling strength is a function of the detuning of the coherent electromagnetic radiation from the transition (Page 5, third paragraph - Page 6, first paragraph: "The coherence time of the hyperfine qubit in Yb+ is long on the time scale of qubit operations and is essentially limited by the coherence time of microwave radiation used to drive the qubit transition. In addition to the ability to perform arbitrary single-qubit operations, a second fundamental type of operation is required for QIP: conditional quantum dynamics with, at least, two qubits. … Thus, it is necessary to couple external (motional) and internal degrees of freedom. Common to all experiments performed to date – related either to QIP or other research fields – that require some kind of coupling between internal and external degrees of freedom of atoms is the use of optical radiation for this purpose. … Therefore, in usual traps, driving radiation in the optical regime is necessary to couple internal and external dynamics of trapped atoms. The distance between neighboring ions δz in a linear electrodynamic ion trap is determined by the mutual Coulomb repulsion of the ions and the time averaged force exerted on the ions by the electrodynamic trapping field. Manipulation of individual ions is usually achieved by focusing electromagnetic radiation to a spot size much smaller than δz. Again, only optical radiation is useful for this purpose. In section 6.2 a new concept for ion traps is described that allows for experiments requiring individual addressing of ions and conditional dynamics with several ions even with radiation in the radio frequency (rf) or microwave (mw) regime. … Thus, individual addressing for the purpose of single qubit operations becomes possible using long-wavelength radiation. At the same time, a coupling term between internal and motional states arises even when rf or mw radiation is applied to drive qubit transitions" teaches applying an electromagnetic radiation signal (one or more signals from signal source) that drive qubit transitions between quantum states (e.g. quantum mechanically evolve the quantum state) based on (under the influence of) couplings and interactions between the atoms/qubits (quantum systems)).
Sete et al., Choi et al., Ebadi et al., and Wunderlich et al. are analogous to the claimed invention because they are directed towards quantum computing.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate the couplings comprise coherent electromagnetic radiation driving a transition between the first state and the second state and the coupling strength is a function of the detuning of the coherent electromagnetic radiation from the transition as taught by Wunderlich et al. to the disclosed invention of Sete et al. in view of Choi et al. and further in view of Ebadi et al.
One of ordinary skill in the art would have been motivated to make this modification to allow electromagnetic radiation to be used instead of laser light for coherent manipulation of a collection of ions because "The interaction with electromagnetic radiation allows for preparation and detection of quantum states, even of single ions" (Wunderlich et al. Page 2, second paragraph).
Conclusion
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/BRIAN J HALES/Examiner, Art Unit 2125
/KAMRAN AFSHAR/Supervisory Patent Examiner, Art Unit 2125