DETAILED ACTION
This office action addresses Applicant’s response filed on 27 February 2026. Claims 1-4, 7-13, and 16-20 are pending.
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 1-4, 7-13, 16, and 17 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
Claims 1 and 11 have been amended to recite that “an attenuation constant of the first substrate is at least one order of magnitude lower than an attenuation constant of the second substrate thereby reducing qubit energy decay associated with the Purcell effect”, which is not supported by the originally-filed disclosure. The Specification discloses that the reduction of qubit energy decay from the Purcell effect is from the inclusion of the Purcell filter, not from the ratio of attenuation constants (¶42). There is no disclosure of any relationship between the ratio of the attenuation constants of the first and second substrates and qubit energy decay through the Purcell effect; in fact, Applicant’s use of the second substrate is not due to the Purcell effect to begin with, let alone a second substrate having an attenuation constant having a particular ratio to the attenuation constant of the first substrate.
Claims 2 and 12 recite that the first Purcell filter has a quality factor less than about 103, which is not supported by the originally-filed disclosure. The disclosure does not specify the quality factor. Applicant cites ¶64 of the Specification, but the cited paragraph merely says that the Purcell filter “inherently has a low quality factor”, and does not specify that the quality factor must be “less than about 103”, as claimed.
Claim 12 also still recites that the first and second substrates have attenuation constants within certain ranges “at a frequency between 5 GHz and 7 GHz”, which is not supported by the originally-filed disclosure. The disclosure is entirely silent on the claimed frequencies. Applicant points to ¶¶59-61, to support the amendments, but the cited paragraphs have no disclosure of the attenuation constants being specifically “at a frequency between 5 GHz and 7 GHz”. Unlike claims 1 and 18, claim 12 has not been amended to remove these limitations.
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, 4, and 8-10 is/are rejected under 35 U.S.C. 103 as being unpatentable over Bronn (US 2020/0250565) in view of Vodrahalli (US 10,525,809) and Intel (“AN 672: Transceiver Link Design Guidelines for High-Gbps Data Rate Transmission”).
Regarding claim 1, Bronn discloses a qubit system, comprising: a qubit located on a first substrate; a readout resonator coupled to the qubit; and a first Purcell filter having a first pole coupled to the readout resonator and located on a second substrate that is physically separate from the first substrate, wherein the second substrate comprises a higher-loss substrate (Fig. 3; ¶38). Bronn does not appear to explicitly disclose that the first substrate comprises a low-loss substrate, wherein an attenuation constant of the first substrate is at least one order of magnitude lower than an attenuation constant of the second substrate thereby reducing qubit energy decay associated with the Purcell effect. Vodrahalli teaches that the first substrate comprises a low-loss substrate (Abstract) and Intel teaches that the second, higher-loss substrate taught by Bronn has attenuation constants >0.1 (Fig. 2). Since the prior art combination has first and second substrates where the first substrate has an attenuation constant at least one order of magnitude lower than the attenuation constant of the second substrate, the prior art combination also satisfies the limitation of “thereby reducing the qubit energy decay associated with the Purcell effect”, since the claim recites that the reduction of the qubit energy decay results from the substrate attenuation constant relationships. See also MPEP § 2112.01(I).
It would have been obvious to persons having ordinary skill in the art before the effective filing date of the application to combine the teachings of Bronn, Vodrahalli, and Intel, because doing so would have involved merely the routine combination of known elements according to known techniques to produce merely the predictable results of using low-loss substrates for qubits. KSR Int’l Co. v. Teleflex Inc., 82 U.S.P.Q.2d 1385, 1395. Bronn discloses a quantum device including a qubit coupled to a resonator, and a filter implemented off-chip, such as on PCBs. Intel teaches that PCBs have attenuation constants >0.1, as taught by Intel. Vodrahalli teaches that the qubit is implemented on a low-loss substrate having attenuation constants <=1x10-5. The teachings of Intel and Vodrahalli are directly applicable to Bronn in the same way, so that Bronn would similarly use lower-loss substrates for qubits to improve qubit implementation.
Regarding claim 4, Bronn does not appear to explicitly disclose that the attenuation constant of the second substrate is at least 100 times more than that of the first substrate. However, as discussed above with regard to claim 1, Intel teaches that the second, higher-loss substrate taught by Bronn has attenuation constants >0.1 (Fig. 2), and Vodrahalli teaches that the first low-loss substrate has an attenuation constant no greater than 1x10-5 (Abstract). Motivation to combine remains consistent with claim 1.
Regarding claim 8, Bronn discloses that the first Purcell filter is implemented in stripline (¶38).
Regarding claim 9, Bronn discloses that the second substrate is on a chip that is separate from that of the first substrate (¶38).
Regarding claim 10, Bronn discloses that the second substrate is on a printed circuit board (PCB) that is separate from that of the first substrate (¶38).
Claim(s) 7 is/are rejected under 35 U.S.C. 103 as being unpatentable over Bronn in view of Vodrahalli, Intel, Abraham (US 2016/0112031), and Zheng (US 2023/0138353).
Regarding claim 7, Bronn does not appear to explicitly disclose a second Purcell filter, configured to provide an additional pole, coupled between the readout resonator and the first Purcell filter, wherein the second Purcell filter is on a substrate having an attenuation constant the same as the first substrate. Abraham discloses a second Purcell filter, configured to provide an additional pole, coupled between the readout resonator and the first Purcell filter (Fig. 6). Zheng teaches that the second Purcell filter is on a substrate having an attenuation constant the same as the first substrate (¶39). It would have been obvious to persons having ordinary skill in the art before the effective filing date of the application to combine the teachings of Bronn, Vodrahalli, Intel, Abraham, and Zheng, because doing so would have involved merely the routine combination of known elements according to known techniques to produce merely the predictable results of incorporating additional filters on-chip to further reduce Purcell effect losses. KSR Int’l Co. v. Teleflex Inc., 82 U.S.P.Q.2d 1385, 1395. Bronn discloses a quantum device including a qubit coupled to a resonator and filter. Abraham teaches that multiple Purcell filters can be coupled to reduce Purcell effect losses. Zheng teaches that the Purcell filter can be implemented on-chip. The teachings of Abraham and Zheng are directly applicable to Bronn in the same way, so that Bronn would similarly include additional Purcell filters on-chip to further reduce Purcell effect losses.
Claim(s) 11 is/are rejected under 35 U.S.C. 103 as being unpatentable over Bronn, Zheng, Vodrahalli, and Intel.
Regarding claim 11, Bronn discloses a method of interacting with a qubit, comprising: providing a qubit on a first substrate; coupling a readout resonator to the qubit; and providing the first Purcell filter on a second substrate that is physically separate from the first substrate, the second substrate comprising a higher-loss substrate (Fig. 3; ¶38). Bronn does not appear to explicitly disclose that the readout resonator is on the first substrate; Zheng discloses the same (Figs. 1 and 2A-C; ¶39). It would have been obvious to persons having ordinary skill in the art before the effective filing date of the application to combine the teachings of Bronn and Zheng, because doing so would have involved merely the routine combination of known elements according to known techniques to produce merely the predictable results of integrating a qubit and its readout element. KSR Int’l Co. v. Teleflex Inc., 82 U.S.P.Q.2d 1385, 1395. Bronn discloses a quantum device including a qubit and a readout resonator. Zheng teaches that the qubit and readout resonator are implemented on the same substrate. The teachings of Zheng are directly applicable to Bronn in the same way, so that Bronn would similarly integrate the qubit and its readout element on the same substrate.
Bronn does not appear to explicitly disclose that the first substrate is a low-loss substrate, and selecting the first and second substrate such that an attenuation constant of the second substrate is greater than 10 times an attenuation constant of the first substrate thereby reducing qubit energy decay associated with the Purcell effect. Vodrahalli teaches that the first substrate comprises a low-loss substrate (Abstract) and Intel teaches that the second, higher-loss substrate taught by Bronn has attenuation constants >0.1 (Fig. 2). Since the prior art combination has first and second substrates where the first substrate has an attenuation constant at least one order of magnitude lower than the attenuation constant of the second substrate, the prior art combination also satisfies the limitation of “thereby reducing the qubit energy decay associated with the Purcell effect”, since the claim recites that the reduction of the qubit energy decay results from the substrate attenuation constant relationships. See also MPEP § 2112.01(I).
It would have been obvious to persons having ordinary skill in the art before the effective filing date of the application to combine the teachings of Bronn, Zheng, Vodrahalli, and Intel, because doing so would have involved merely the routine combination of known elements according to known techniques to produce merely the predictable results of using low-loss substrates for qubits. KSR Int’l Co. v. Teleflex Inc., 82 U.S.P.Q.2d 1385, 1395. Bronn discloses a quantum device including a qubit coupled to a resonator, and a filter implemented off-chip, such as on PCBs. Intel teaches that PCBs have attenuation constants >0.1, as taught by Intel. Vodrahalli teaches that the qubit is implemented on a low-loss substrate having attenuation constants <=1x10-5. The teachings of Intel and Vodrahalli are directly applicable to Bronn in the same way, so that Bronn would similarly use lower-loss substrates for qubits to improve qubit implementation.
Regarding claim 13, Bronn does not appear to explicitly disclose that the second substrate has an attenuation constant that is at least 100 times more than that of the first substrate. However, as discussed above with regard to claim 11, Intel teaches that the second, higher-loss substrate taught by Bronn has attenuation constants >0.1 (Fig. 2), and Vodrahalli teaches that the first low-loss substrate has an attenuation constant no greater than 1x10-5 (Abstract). Motivation to combine remains consistent with claim 11.
Regarding claim 17, Bronn discloses housing the qubit, the readout resonator, and the first Purcell filter in a cryogenic environment (Fig. 3).
Claim(s) 16 is/are rejected under 35 U.S.C. 103 as being unpatentable over Bronn in view of Zheng, Vodrahalli, Intel, and Abraham.
Regarding claim 16, Bronn does not appear to explicitly disclose coupling a second Purcell filter between the readout resonator and the first Purcell filter, wherein the second Purcell filter is on a substrate having an attenuation constant the same as the first substrate. Abraham discloses coupling a second Purcell filter between the readout resonator and the first Purcell filter (Fig. 6). Zheng teaches that the second Purcell filter is on a substrate having an attenuation constant the same as the first substrate (¶39). It would have been obvious to persons having ordinary skill in the art before the effective filing date of the application to combine the teachings of Bronn, Vodrahalli, Intel, Abraham, and Zheng, because doing so would have involved merely the routine combination of known elements according to known techniques to produce merely the predictable results of incorporating additional filters on-chip to further reduce Purcell effect losses. KSR Int’l Co. v. Teleflex Inc., 82 U.S.P.Q.2d 1385, 1395. Bronn discloses a quantum device including a qubit coupled to a resonator and filter. Abraham teaches that multiple Purcell filters can be coupled to reduce Purcell effect losses. Zheng teaches that the Purcell filter can be implemented on-chip. The teachings of Abraham and Zheng are directly applicable to Bronn in the same way, so that Bronn would similarly include additional Purcell filters on-chip to further reduce Purcell effect losses.
Claim(s) 18-20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Zheng in view of Abraham, Bronn, Intel, and Vodrahalli.
Regarding claim 18, Zheng discloses a qubit device, comprising: a qubit located on a first substrate comprising a low-loss dielectric substrate; a readout resonator coupled to the qubit and located on the first substrate (Figs. 1 and 2A-C, ¶¶39, 47, 48); a first filter configured to provide a first pole coupled to the readout resonator, the first filter being located on the first substrate (Fig. 2A-B). Zheng does not appear to explicitly disclose that the filter is a Purcell filter; a second Purcell filter coupled to an output of the first Purcell filter and located on a second substrate that is physically separate from the first substrate, the second substrate comprising a higher-loss substrate.
Abraham discloses a qubit device, comprising: a qubit located on a first substrate (Fig. 1, qubit 150); a readout resonator coupled to the qubit and located on the first substrate (Fig. 1, readout resonator 160); a first Purcell filter configured to provide a first pole coupled to the readout resonator, the first Purcell filter being located on the first substrate (Fig. 1, notch filter 110; ¶27); and a second Purcell filter coupled to an output of the first Purcell filter (Fig. 6). Bronn teaches that the second Purcell filter is located on a second substrate that is physically separate from the first substrate, the second substrate comprising a higher-loss substrate (¶¶11, 38). It would have been obvious to persons having ordinary skill in the art before the effective filing date of the application to combine the teachings of Zheng, Abraham, and Bronn, because doing so would have involved merely the routine combination of known elements according to known techniques to produce merely the predictable results of incorporating additional filters off-chip to further reduce Purcell effect losses. KSR Int’l Co. v. Teleflex Inc., 82 U.S.P.Q.2d 1385, 1395. Zheng discloses a quantum device including a qubit coupled to a resonator and filter. Abraham teaches that the filter is a Purcell filter and that multiple Purcell filters can be coupled to reduce Purcell effect losses. Bronn teaches that the Purcell filter can be implemented off-chip, such as on a separate chip or PCB. The teachings of Abraham and Bronn are directly applicable to Zheng in the same way, so that Zheng would similarly include additional Purcell filters off-chip to further reduce Purcell effect losses.
Zheng does not appear to explicitly disclose the attenuation constant of the second substrate is greater than 10 times an attenuation constant of the first substrate. However, Intel teaches that the second, higher-loss substrate taught by Bronn has attenuation constants >0.1 (Fig. 2), and Vodrahalli teaches that the first low-loss substrate has an attenuation constant no greater than 1x10-5 (Abstract). It would have been obvious to persons having ordinary skill in the art before the effective filing date of the application to combine the teachings of Zheng, Abraham, Bronn, Intel, and Vodrahalli, because doing so would have involved merely the routine combination of known elements according to known techniques to produce merely the predictable results of using low-loss substrates for qubits. KSR Int’l Co. v. Teleflex Inc., 82 U.S.P.Q.2d 1385, 1395. Zheng discloses a quantum device including a qubit coupled to a resonator and filter. As discussed above, Bronn teaches that filters can be implemented off-chip, such as on PCBs, which have attenuation constants >0.1, as taught by Intel. Vodrahalli teaches that the qubit is implemented on a low-loss substrate having attenuation constants <=1x10-5. The teachings of Intel and Vodrahalli are directly applicable to Zheng in the same way, so that Zheng would similarly use lower-loss substrates for qubits to improve qubit implementation.
Regarding claim 19, Zheng does not appear to explicitly disclose that the attenuation constant of the second substrate is at least 100 times more than that of the first substrate. However, as discussed above with regard to claim 18, Intel teaches that the second, higher-loss substrate taught by Bronn has attenuation constants >0.1 (Fig. 2), and Vodrahalli teaches that the first low-loss substrate has an attenuation constant no greater than 1x10-5 (Abstract). Motivation to combine remains consistent with claim 18.
Regarding claim 20, Zheng does not appear to explicitly disclose that the second substrate is a printed circuit board (PCB) that is separate from the first substrate; Bronn discloses these limitations (¶38).
Response to Arguments
Applicant's arguments filed 27 February 2026 have been fully considered but they are not persuasive.
As an initial matter, new limitations are addressed above in the new grounds of rejection, and are not further discussed here.
Applicant asserts that Abraham fails to teach selecting substrate materials based on an attenuation ratio, Zheng fails to teach the substrate attenuation differential, and that Bronn and Vodrahalli merely recognize that low-loss materials are desirable for qubits and that filtering is beneficial, and so none of the references teach selecting the attenuation constants to differ by at least an order of magnitude to reduce Purcell-related delay. Remarks 9. The examiner disagrees. Vodrahalli teaches using low-loss substrates for the qubits, while Bronn teaches using separate, high-loss substrates such as PCBs for the Purcell filter, and the attenuation constants of Vodrahalli’s qubit substrate and Bronn’s filter substrate differ by at least an order of magnitude. Further, since the claim recites that the reducing of Purcell-related delay results from the attenuation constants differing by at least an order of magnitude, the prior art also satisfies that limitation by teaching attenuation constants differing by at least an order of magnitude.
Conclusion
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4 April 2026
/ARIC LIN/ Examiner, Art Unit 2851