DETAILED ACTION
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 25 August 2026 has been entered.
Response to Arguments
Applicant’s arguments with respect to claim(s) 1-2, 4-5, 7-12, 14-15 and 17-20 have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
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 1-2, 4-5, 7-12, 14-15 and 17-20 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 determined optical SBC detuning frequency" in lines 22-23. There is insufficient antecedent basis for this limitation in the claim. It is not clear whether this is the obtained detuning frequency from lines 4-5 or a separate determined frequency.
The same issue exists in claim 17 and is vague and indefinite for the same reasons.
All dependent claims are vague and indefinite by virtue of their dependencies on rejected independent claims 1 and 17.
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.
Claim(s) 1-2, 4-5, 7-12, 14-15 and 17-20 are rejected under 35 U.S.C. 103 as being unpatentable over Chen (Chen et al., Efficient sideband cooling protocol for long trapped-ion chains, 2020) (copy of publication submitted with the office action of 30 April 2025) in view of Debenath et al. (US pgPub 2020/0321949).
Regarding claim 1, Chen teaches a method for side-band cooling a trapped ion chain that includes a plurality of qubits in a trap of quantum computing system (page 2, left column, last paragraph “a seven ion chain where the middle five ions are evenly spaced…the middle set of five …are individually addressed by the Raman laser system”, last paragraph on page 1 teaches “resolved sideband cooling of a given mode involves tuning the Raman lasers”. Title teaches long trapped-ion chains, page 2, left column, last paragraph teaches the middle set of five ions serve as qubits in a computation), comprising:
applying an analysis pulse on each qubit of at least a subset of qubits of the plurality of qubits of the trapped ion chain to obtain an optimal detuning frequency and an optimal SBC pulse duration from a first batch of SBC pulse sequences (last paragraph, left column on page 2 teaches resolved sideband cooling proceeds after Doppler using the center five addressable ions to cool all seven modes of interest. fig. 1 shows mapping, right column first full paragraph on page 2 teaches applying two to three sideband cooling sequencies, where each sequence cools a predefined set of modes…We determine the composition of a given sequence to improve cooling efficiency on higher heating modes, where each cooling sequence has at least one ion cooling the highest heating modes” That is, the initial sequence is interpreted to be analysis pulses resulting in the diagram of figure 1. See also “supplemental material” on page 5, which discusses a first round of cooling and a second round of cooling, wherein the second round adjusts the transverse modes to achieve better cooling results (i.e. suggesting analysis of the first round of cooling). Lastly, note supplemental material identifies m0 has the largest detuning (i.e. optimal) and increasing duration decreases phonon Frock states (i.e. optimal duration). Note the optimal detuning and duration is applied in the experiment, thus obtained by the experiment) that include:
a repetition of pulses at a plurality of detuning points that drive each qubit of the subset of qubits from a state |0> to a state |1>, wherein the plurality of detuning points span a set of frequencies of a motional spectra that the quantum computing system is being configured to cool (fig. 1 and supplemental materials note: first round of pulses for detuning at points m0-m6, note because the states must be repumped between SBC pulse to a ground state (I↓>) the each qubit of the subset is driven to a higher state (|1>). . Page 2, right column second paragraph teaches applying two or three sideband cooling sequencies, where each sequence cools a predefined set of modes using a subset of addressable ions. See page 2 second paragraph on right column for high fidelity quantum computation),
and a duration scan in parallel to each qubit of the subset of qubits (page 2, left column, first full paragraph teaches ions can be driven with individually controlled Raman beam frequences, this process can be parallelized by driving each ion with a separate frequency. The following paragraph teaches the middle set of five ions (subset) are individually addressed by the Raman laser system (i.e. scan (inherently having a duration) in parallel to each qubit)) and at the plurality of detuning points to determine the optimal SBC pulse duration for each qubit of the subset of qubits at which a qubit flip from the initial state |0> to the state |1> is maximized for the respective detuning point (supplemental material teaches “We apply 40 of these pulses with increasing duration, increasing duration, timed to the transition time [[i.e. change of state]] for decreasing phonon Fock states in the specified mode (associated with detuning i.e. claimed detuning points are the specified modes) driven by the specified qubit.” That is, an optimal duration at the time of transition to decrease phonon fock states at modes having detuning points as evidenced by “mode 6…has the smallest detuning” (see supplemental material));
defining at least one additional batch of successive SBC pulse sequences (supplemental material, second round is the same as the first round) that is based on the obtained optimal SBC detuning frequency and the optimal SBC pulse duration obtained for the first batch of SBC pulse sequences (supplemental material, second round the same as the first round using mode m0 twice thus using the largest detuning, wherein the increasing duration is re-applied thus including the optimal pulse duration);
applying an optical pumping operation that resets at least the subset of qubits to the state |0> (second round the same as the first round, prior to first round Doppler cooling and doppler cooling in between each side band cooling pulse (see supplemental material). Thus a return to ground state prior to second round); and
applying at least one additional analysis pulse on each qubit of the subset of qubits (second round see supplemental material) and incrementally applying the defined at least one additional batch of successive SBC pulse sequences (40 pulses in second round sequence see supplemental material) that is based on the first batch (same as the first batch thus based on the first batch) to determine an SBC cooling routine for the quantum computing system (page 2 right column second paragraph teaches “we determine the composition of a given sequence to improve cooling efficiency…for high-fidelity quantum computation” thus by determining the composition of the sequence Chen determines the SBC cooling routine for the quantum computing system) that includes the determined optical SBC detuning frequency and the optimal SBC pulse duration obtained by the at least one additional analysis pulse on each qubit and at which a probability of flipping the state of each qubit from the state 0 to 1 is maximized (supplemental material, second round the same as the first round using mode m0 twice thus using the largest detuning, wherein the increasing duration is re-applied thus including the optimal pulse duration. That is, highest detuning and optimal duration are obtained through experiment and such results in maximum flipping state of each qubit (i.e. transition) such that high fidelity quantum computation is achieved. Note page 2, right column, second paragraph additionally envisions using three sequences, thus including the optimal detuning frequency and pulse duration of previous sequence).
Chen teaches that in the second round is the same as the first round and therefore fails to disclose applying a reduced optical pumping operation such that a first duration of the optical pumping operation is longer than a second duration of the reduced optical pumping operation.
However, Debnath et al. teaches a reduced optical pumping operation such that a first duration of the optical pumping operation is longer than a second duration of the reduced optical pumping operation (fig. 15 shows a cyclic flow chart to optimize the gate duration ([0082]), wherein by iterating steps 1502-1506 an optimal value of the gate duration is determined ([0087]). The gate duration has a starting point, wherein it has been observed that while reducing the gate duration factor (i.e. shortening the gate duration as evidenced by the equation in [0087]), the detuning induced infidelity is reduced. That is, the pulse duration is initially longer in the first round of the flow chart and is reduced in the second round to observe reduced detuning induced infidelity).
Debnath modifies Chen by suggesting reducing the length of a second duration relative to the first (i.e. reducing the pulse duration of Chen in the second round relative to the first).
Since both inventions are directed towards reducing infidelity or producing high fidelity quantum computation, it would have been obvious to one of ordinary skill in the art to apply the shortened gate duration (i.e. pulse duration), in the second round of Chen as suggested by Debnath because it would reduce infidelity at optimal values of the detuning, therefore improving the high fidelity or the probability that at least two ions are in the intended quantum states ([0035] and [0087]).
Regarding claim 2, Chen teaches wherein the first cooling is a doppler cooling (Supplemental material on page 5, see left column, first paragraph).
Regarding claim 4, Chen teaches wherein the plurality of detuning points are based on a detuning set that spans red side-band transition frequencies for transverse motional modes in the trapped ion chain (paragraph bridging pages 1-2 teaches red sideband transition with the Raman lasers and left column, last paragraph on page 2 teaches sideband cooling all seven modes of interest (namely, one set of transverse modes”).
Regarding claim 5, Chen teaches wherein the detuning set includes evenly spaced frequencies (page 2, left column last paragraph teaches evenly spaced ions, therefore the parallel applied frequencies are evenly spaced by the distance between ions).
Regarding claim 7, Chen teaches wherein a number of cooling ions in the trapped ion chain is less than a total number of ions in the trapped ion chain (5 of 7 see page 2, left column, last paragraph ).
Regarding claim 8, Chen teaches varying the number of cooling ions in the trapped ion chain for the SBC pulse sequence based on when the SBC pulse sequence is applied (page 2, right column, last paragraph teaches cool ion chains with a varying number of ions ranging from 5-25 ions. While the number of ions grows, the number of cooling pulses needed remains nearly constant using the parallel scheme and thus the time is the same if the pulse duration is the same. That is, the number of ions (i.e. for cooling by sideband cooling pulse sequency) grows (varies) based on when the side-band cooling pulse sequence is applied (i.e. increasing from 5-25 ions after applying the ions to 5)).
Regarding claim 9, Chen teaches wherein the first batch of SBC pulse sequences includes between 1 and 5 SBC cooling pulses (supplemental materials any 1-5 of the 40 pulses applied in the sequences in first and second batch. See also page 2, right column, first paragraph for two or three side band cooling sequences)
Regarding claim 10, Chen teaches performing one or more quantum computations using the trapped ion chain after obtaining the optimal detuning frequency and the optimal SBC pulse duration (page 2, right column first full paragraph, last sentence teaches motional states cold enough for high fidelity quantum computation, thus quantum computation occur after).
Regarding claim 11, Chen teaches the functional claimed limitations as discussed above. Moreover, Chen teaches a quantum computer (abstract) configured to perform side-band cooling of a trapped ion chain (page 2, left column, last paragraph), comprising: a trap configured to hold multiple ions in a trapped ion chain (page 2, left column, last paragraph); and one or more controllers (inherent to control the detuning and pulse durations, see specific reference to sections discussed above in claim 1).
Claims 12, 14-15 and 17-20 are commensurate in scope with claims 2-8 and 10 and rejected as discussed herein above.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Amini (US pgPub 2020/0005178) suggests applying doppler cooling followed by SBC ([0054] and discussion in Non-Final Rejection of 30 April 2020)
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/MICHAEL J LOGIE/Primary Examiner, Art Unit 2881
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