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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 04/22/2026 has been entered.
Response to Amendment
The office action is responding to the amendments filed on 03/31/2026. Claims 1, 9, 14-15, 17 and 19 have been amended. Claims 2-3 and 18 are cancelled.
Claim Rejections - 35 USC § 103
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.
Claim(s) 1, 4-13 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kerman et al. [US 2017/0141286 A1] in view of Caudillo et al. [US 2019/0044051 A1] and in further view of Chow et al. [US 2018/0225586 A1].
Claim 1 is rejected over Kerman, Caudillo and Chow.
Karman teaches “An electronic structure, comprising: a first Superconducting Quantum Interference Device (SQUID) coupled between a first pad and a second pad of a first tunable coupler qubit (TCQ), and” as [Fig. 2] (Fig. 2 shows a SQUID device coupled to plurality of Qubits)
“a first Josephson Junction (JJ) coupled between the second pad and a third pad of the first TCQ; and” as “According to one aspect of the disclosure, a system for multiqubit interaction includes: a multispin coupler including a plurality of loops, each loop having a pair of Josephson junctions; and a plurality of qubits each inductively coupled to the multispin coupler.” [¶0007]
Karman does not explicitly teach a second SQUID coupled between a first pad and a second pad of a second TCQ, and a second JJ coupled between the second pad and a third pad of the second TCQ,
wherein the second pad of the first TCQ is coupled to the second pad of the second TCQ; and the first TCQ is coupled to a first driveline; and the second TCQ is coupled to a second driveline, wherein the first TCQ is coupled with the second TCQ via direct capacitive coupling or with a coplanar waveguide resonator in a pad to line to pad coupling arrangement.
However, Caudillo teaches “a second SQUID coupled between a first pad and a second pad of a second TCQ, and a second JJ coupled between the second pad and a third pad of the second TCQ,” as “FIG. 2 illustrates a quantum circuit assembly 200 showing a vertical SQUID loop 210 of a single qubit 102, provided over a substrate 214. The substrate 214 may be any substrate suitable for realizing quantum circuit assemblies described herein.” [¶0062]
“wherein the second pad of the first TCQ is coupled to the second pad of the second TCQ; and the first TCQ is coupled to a first driveline; and the second TCQ is coupled to a second driveline,” as “FBLs, microwave lines, readout lines, drive lines, coupling components, and readout resonators, such as e.g., those described above, together form interconnects for supporting propagation of microwave signals. Further, any other connections for providing direct electrical interconnection between different quantum circuit elements and components, such as e.g., connections from electrodes of Josephson Junctions to plates of the capacitors or to superconducting loops of SQUIDs or connections between two ground lines of a particular transmission line for equalizing electrostatic potential on the two ground lines, may also be referred to as interconnects.” [¶0055]
Karman and Caudillo are analogous arts because they teach quantum computing system and architecture.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention, having the teachings of Karman and Caudillo before him/her, to modify the teachings of Karman to include the teachings of Caudillo with the motivation of implementing vertical FBLs and vertical SQUID loops as described herein may advantageously facilitate use of three-dimensional (3D) and stacked designs for quantum circuit assemblies and may be particularly advantageous for realizing device scalability and use of 300-millimeter fabrication processes. [Caudillo, ¶0023]
The combination of Karman and Caudillo does not explicitly teach wherein the first TCQ is coupled with the second TCQ via direct capacitive coupling or with a coplanar waveguide resonator in a pad to line to pad coupling arrangement.
However, Chow teaches “wherein the first TCQ is coupled with the second TCQ via direct capacitive coupling or with a coplanar waveguide resonator in a pad to line to pad coupling arrangement.” as “In FIG. 1A, in system 100, there are two qubits, a control qubit (Q.sub.C) 110 and a target qubit (Q.sub.T) 120, coupled through a bus 130 (also called a bus resonator), which is a superconducting coplanar waveguide resonator.” [¶0028]
Kerman, Caudillo and Chow are analogous arts because they teach quantum computing system and architecture.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention, having the teachings of Kerman, Caudillo and Chow before him/her, to modify the teachings of combination of Karman and Caudillo to include the teachings of Chow with the motivation of the CR gate fidelity for the same gate time is f=0.948±0.018 (e.g., as compared with a CR gate fidelity f=0.991±0.002 with the cancellation tone), demonstrating that the additional drive effectively cancels out the error terms of the CR Hamiltonian. It is noted that the article by C. Rigetti and M. Devoret (Phys. Rev. B 81, 134507 (2010)) provides a good introduction to operation of a two-qubit conventional system. [Chow, ¶0032]
Claim 4 is rejected over Kerman, Caudillo and Chow.
Karman does not explicitly teach wherein the first TCQ includes a first oscillation mode and a second oscillation mode; the second TCQ includes a third oscillation mode and a fourth oscillation mode; and quantum information is capable of being stored in the first oscillation mode of the first TCQ and the third oscillation mode of the second TCQ.
However, Caudillo teaches “wherein the first TCQ includes a first oscillation mode and a second oscillation mode; the second TCQ includes a third oscillation mode and a fourth oscillation mode; and quantum information is capable of being stored in the first oscillation mode of the first TCQ and the third oscillation mode of the second TCQ.” as “a readout resonator may either have a capacitive connection to ground (for a half-wavelength resonator) or may have a short circuit to the ground (for a quarter-wavelength resonator), which also results in oscillations within the transmission line, with the resonant frequency of the oscillations being close to the frequency of the qubit.” [¶0047]
Claim 5 is rejected over Kerman, Caudillo and Chow.
Karman teaches “wherein the first SQUID is flux-tunable via the first driveline, and the second SQUID is flux-tunable via the second driveline.” as “the multispin coupler can be configured to operate in either an energy mode or a current mode by adjusting a magnetic flux through one or more of the loops of the multispin coupler.” [¶0007]
Claim 6 is rejected over Kerman, Caudillo and Chow.
Karman teaches “wherein the first SQUID includes a first plurality of JJs; the second SQUID includes a second plurality of JJs; a first sum of critical currents from the first plurality of JJs is substantially similar to a first critical current of the first JJ; and a second sum of critical currents from the second plurality of JJs is substantially similar to a second critical current of the second JJ.” as “According to another aspect of the disclosure, a system for multiqubit interaction includes: a first multispin coupler; a plurality of second multispin couplers each inductively coupled to the first multispin coupler, wherein the first multispin coupler and each of the plurality of second multispin couplers include a plurality of loops, each loop having a pair of Josephson junctions; and a plurality of qubits coupled to each of the second multispin couplers.” [¶0008]
Claim 7 is rejected over Kerman, Caudillo and Chow.
Karman does not explicitly teach wherein the second oscillation mode of the first TCQ is coupled to the fourth oscillation mode of the second TCQ.
However, Caudillo teaches “wherein the second oscillation mode of the first TCQ is coupled to the fourth oscillation mode of the second TCQ.” as “a readout resonator may either have a capacitive connection to ground (for a half-wavelength resonator) or may have a short circuit to the ground (for a quarter-wavelength resonator), which also results in oscillations within the transmission line, with the resonant frequency of the oscillations being close to the frequency of the qubit.” [¶0047]
Claim 8 is rejected over Kerman, Caudillo and Chow.
Karman teaches “wherein the first TCQ and the second TCQ are capable of performing a controlled phase gate.” as “In particular, the constant phase offset between each Josephson junction can be controlled to realize arbitrary potential energy function vs. uniform flux.” [¶0027]
Claim 9 is rejected over Kerman, Caudillo and Chow under the same rationale of rejection of claim 1.
Claim 10 is rejected over Kerman, Caudillo and Chow under the same rationale of rejection of claim 4.
Claim 11 is rejected over Kerman, Caudillo and Chow under the same rationale of rejection of claim 5.
Claim 12 is rejected over Kerman, Caudillo and Chow under the same rationale of rejection of claim 6.
Claim 13 is rejected over Kerman, Caudillo and Chow under the same rationale of rejection of claim 4.
Allowable Subject Matter
The following is an examiner’s statement of reasons for allowance: Independent claim 14 recites: “applying the first flux, via the first driveline, to a first SQUID of the first TCQ to lower a Josephson energy of the first SQUID and to change a spatial configuration of a first oscillation mode and a second oscillation mode of the first TCQ.”
Closest prior arts Kerman et al. [US 2017/0141286 A1], Caudillo et al. [US 2019/0044051 A1] and Chow et al. [US 2018/0225586 A1] neither individually nor in any combination, teaches or suggests “applying the first flux, via the first driveline, to a first SQUID of the first TCQ to lower a Josephson energy of the first SQUID and to change a spatial configuration of a first oscillation mode and a second oscillation mode of the first TCQ,” as presently claimed. In particular, the cited references generally disclose superconducting qubit structures, tunable couplers, and flux-based qubit control techniques, but fail to disclose or suggest selectively applying flux through a dedicated driveline to a specific SQUID of a tunable coupling qubit (TCQ) in a manner that both lowers the Josephson energy of that SQUID and changes the spatial configuration of multiple oscillation modes of the TCQ. The references do not teach the claimed coordinated relationship between flux application, modification of SQUID Josephson energy, and resultant spatial reconfiguration of first and second oscillation modes within the TCQ architecture. Accordingly, the claimed limitation is considered to be neither taught nor rendered obvious by the cited prior art. Based on this rationale, claim 14 and its dependent claims 15-17 and 19-20 are allowed.
Any comments considered necessary by applicant must be submitted no later than the payment of the issue fee and, to avoid processing delays, should preferably accompany the issue fee. Such submissions should be clearly labeled “Comments on Statement of Reasons for Allowance.”
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MASUD K KHAN whose telephone number is (571)270-0606. The examiner can normally be reached Monday-Friday (8am-5pm).
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/MASUD K KHAN/ Primary Examiner, Art Unit 2132
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