DETAILED ACTION
This action is in response to the Request for Continued Examination (RCE) filed on July 21, 2026. Claims 1, 7, 10, 13, 16-17, 19, 21, and 23 have been amended. Claims 2, 3, 11-12, 18, 20, 22, 24 have been previously canceled and claims 28-32 have been presently canceled. Claims 33-37 are new. Claims 1, 4-10, 13-17, 19, 21, 23, 25-27, and 33-37 are pending. Of such, claims 1, 4-10, 13-16, 21, 23, 25-27, and 33-37 represent apparatus’ and claims 17 and 19 represent methods directed to implementing quantum key distribution in a data center environment.
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 July 21, 2026 has been entered.
Response to Arguments
Applicant's arguments filed July 21, 2026 have been fully considered but they are not persuasive.
Regarding the applicant’s argument I of the remarks, the applicant states that Ma does not disclose a multimode optical fiber channel.
This argument is not persuasive.
The applicant states that Ma labels the fiber as “single-mode” and its higher-order modes are an “incidental artifact”. The claim recites a “multimode optical fiber” not a fiber structurally designed or manufactured for multimode operation. Under broadest reasonable interpretation, a multimode optical fiber is one that guides more than one mode at its operating wavelength. The applicant’s proposed limitation to fiber “structurally designed” for multimode operation is not recited in the claims and is not read into the claims from the specification. Under broadest reasonable interpretation, Ma discloses a multimode optical fiber channel. Ma states “some higher order transverse modes exist in the fiber” in section 3.4. Further, in section 6.2 discloses “SMF-28 cannot provide single mode transmission at 850 nm”. The applicant’s description of higher-order modes as an “incidental artifact” does not distinguish the claims because it concedes that the modes are present in the channel during operation. ‘
The applicant next states that the higher-order-mode photons are filtered by the HI-780 splice before detection, such that qubits are not conveyed multimode from end-to-end. This argument does not meet what is claimed. The claims require transmission via a multimode optical fiber quantum communication channel, they do not require that the qubits arrive at the photon detector in multiple modes.
The applicant further argues that Ma teaches away from a multimode channel. A reference is no less anticipatory if, after disclosing the invention, the reference then disparages it. The question whether a reference “teaches away” from the invention is inapplicable to an anticipation analysis. See MPEP 2131.05. The rejection does not propose to substitute multimode fiber for single-mode components in Ma. The Applicant’s arguments directed to the absence of a teaching or suggestion to make such a substitution, are directed to a modification that is not part of the rejection. Ma presents the mode-filtering technique as one that permits, rather than discourages, 850 nm operation over standard telecom fiber (Ma, Section 3.4).
Regarding applicant’s argument II of the remarks, the applicant states new claims 34 and 37 disclose a quantum memory that Ma fails to disclose.
The examiner agrees with the applicant and the newly added claims 34 and 37 are rejected over Ma in view of Rhee.
Regarding applicant’s argument III of the remarks, the applicant states that Ma does not disclose configuring the on-chip semiconductor laser to attenuate its output to generate single photons as described in claim 35 and ¶ 53 of the applicant’s specification for support.
This argument is not persuasive.
Claim 35 recites that the laser “is configured to attenuate an output of the on-chip semiconductor laser”. Under broadest reasonable interpretation, consistent with the applicant’s specification, the limitation requires that an output of the laser be attenuated to the single-photon level, it does not require that the laser element itself, as a distinct element from an attenuating element associated with the laser, perform the attenuation. The applicant’s own specification describes the limitation at this level of generality by stating the attenuating the semiconductor lasers output is a technique for achieving single-photon emission, without specifying the mechanism by which the output is attenuated. As the claim is constructed, the limitation reads on Ma. In which Ma discloses an 850 nm VCSEL whose output “is then attenuated by variable optical attenuators (VOA) to the single photon level”.
Regarding the applicant’s argument IV of the remarks, the applicant states that Vest does not cure the deficiencies of Ma with respect to claims 4 and 13 wherein Vest is directed to a free-space hand-held system and that the motivation to combine Ma and Vest is insufficient.
This argument is not persuasive.
With respect to claim 4, Vest is relied upon only for the form-factor limitation, where Ma discloses the multimode optical fiber channel and the remaining limitations. The rejection does not propose to convert Ma into a hand-held or free-space system, so the Applicant’s argument that Vest is free-space and lacks an optical fiber channel is directed to a combination that is not made. The rationale for the combination is directed at reduced footprint and cost. With respect to claim 13, the argument is moot as claim 13 is no longer rejected over Ma in view of Vest.
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, 4-10, 13-17, 19, 21, 23, 25-27, and 33-37 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.
Independent claims 1, 10, 17, 19, 21, and 23 were amended to replace “a quantum communication channel” with “a multimode optical fiber quantum communication channel”. The originally filed specification does not reasonably convey that the inventors possessed a quantum communication channel that is a multimode optical fiber. The amendment introduced a limitation narrower than the channel the specification describes.
The applicant identifies ¶¶ 40-42, 53, and 63 as support for the amendment. However, the only paragraph that mentions multimode fiber is ¶ 63 of the specification, which describes photon detector 132 and explains why silicon SPADs suit 850 nm. It’s multimode reference is a statement about the field: “data centers often use wavelengths around 850 nm for short-distance optical communications because standard multimode fiber optics are optimized for this wavelength”, so that using silicon-based SPADs at 850 nm “can leverage existing optical infrastructure”. That sentence describes the multimode fiber plan that data centers already deploy, offered as the reason the 850 nm detector was selected. That statement is not related to pre-existing infrastructure and not a description of the applicant’s own quantum communication channel 106 in which the applicant is claiming is multimode.
Claims 33 and 36 depend on claims 1 and 10 respectively and recite “the multimode optical fiber quantum communication channel comprises a standard multimode optical fiber optimized for optical communication at wavelengths around 850 nm”. This further narrows the previously discussed limitation that lacks written description.
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.
Claim 37 is 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 37 discloses the following limitation “temporarily store quantum information associated with the qubits prior to completion of the decoding of the states of the qubits;” The examiner interprets the claim as a pre-detection temporary store that holds the received qubits, still in their quantum states while the measurement basis is selected and applied. However, the specification is inconsistent with the interpretation as the specification discloses the quantum memory placed within the quantum state measurement circuitry. Which according to Fig 1C, places the quantum memory after detection which contradicts the claim.
Claim Rejections - 35 USC § 102
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 the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claim(s) 1, 5-10, 14-17, 19, 21, 23, 26, and 35 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Ma et al. (NPL: High Speed Quantum Key Distribution Over Optical Fiber Network System), hereinafter referred to as Ma.
Regarding Claim 1, Ma discloses:
A quantum transmitter for use in quantum key distribution (QKD) (In section 3.1, Ma discloses “Fig. 4 shows a schematic diagram of our fiber-based BB84 QKD system, which uses a pair of our PCBs to process the data at a continuous high data rate [13] to create a shared sifted key according to the BB84 protocol.”), the quantum transmitter comprising: a light source configured to generate photons at an operational wavelength of around 850 nm, wherein the light source is an on-chip semiconductor laser (In section 1, Ma discloses “For LANs, our 850 nm QKD system is a good choice, since it uses low-cost Vertical Cavity Surface Emitting Laser (VCSEL) and Silicon avalanche photon detectors (Si-APDs).” And further in section 3.1 “Each of the four outputs drives a 10 Gbit/s 850 nm VCSEL that generates a laser pulse. ”); quantum state preparation circuitry operatively coupled to the light source and configured to (In section 2.2, Ma discloses “These electrical signals are sent from the PCB to the photonics, where they are shaped and converted to optical signals for the classical channel and single photons for the quantum channels.”): receive a sequence of bits (In section 2.2, Ma discloses “The Random Number Generator module on Alice’s FPGA generates two bit-streams of pseudo random data at up to 1.25 Gbit/s each; one stream for the bit value and the other for the basis.”); map the bits to respective quantum states and measurement bases (In section 2.1, Ma discloses “In the BB84 system, each photon is set in one of the four linear polarization states: horizontal-vertical (belonging to the horizontal-vertical basis) or +/- 45 degree diagonal (belonging to the diagonal basis). One of the polarization states in each basis represents a “0” bit value and the other a “1”.”); and encode the quantum states onto respective photons based on the measurement bases to generate qubits (In section 3.1, Ma discloses “A linear polarizer and a half-wave plate (HWP) sets the polarization orientation, −45°, +45°, 0° or 90°, that corresponds to the output path. These four output streams are combined into a single stream by non-polarizing beam-splitters (NPBSs) and then sent to Bob over the quantum channel.”); and a quantum channel interface operatively coupled to the quantum state preparation circuitry (In section 2.2, Ma discloses “Each packet is then passed to the Transmit/Receive module where they are synchronously sent to Bob on the quantum channel along with a “Sync” message on the classical channel.”) and configured to transmit the qubit to a quantum receiver via a multimode optical fiber quantum communication channel (In section 2.2 Ma discloses “When a “Sync” message is received by the Transmit/Receive module in Bob’s FPGA, it begins the capture of one packet’s worth of data from the Quantum channels.” And in Section 6.2, Ma further discloses “SMF-28 cannot provide single mode transmission at 850 nm”).
Regarding Claim 5, Ma discloses:
The quantum transmitter of Claim 1, wherein the quantum transmitter is configured to operate at a room temperature. (In section 5, Ma discloses “Si-APDs are low cost, operate at room temperature and have the highest peak detection efficiency among these detectors”)
Regarding Claim 6, Ma discloses:
The quantum transmitter of Claim 1, further comprising security and protocol management circuitry configured to: transmit, via a classical communication channel, the measurement bases used to encode the bits to the quantum receiver (In section 2.1, Ma discloses “The next three stages of the protocol, common to both BB84 and B92, are conducted over an unsecured public link (called the classical channel, since this can be standard IP communications)… The second stage is sifting, where Bob sends a list back to Alice of photons detected and their basis (measurement state), but not their value.”).
Regarding Claim 7, Ma discloses:
The quantum transmitter of Claim 6, wherein the security and protocol management circuitry is further configured to: receive, from the quantum receiver via the classical communication channel, measurement bases for decoding the qubits (In section 2.1, Ma discloses “Bob randomly chooses to measure the photons in either the horizontal-vertical or diagonal basis… where Bob sends a list back to Alice of photons detected and their basis (measurement state), but not their value.”); and establish a shared encryption key with the quantum receiver using bits and qubits having matching measurement bases (In section 2.1, Ma discloses “Alice and Bob now have a list of sifted keys.”).
Regarding Claim 8, Ma discloses:
The quantum transmitter of Claim 1, wherein a transmission distance between the quantum transmitter and the quantum receiver is less than 2 km. (In section 3.5, Ma discloses “this system can provide more than 4 Mbit/s of sifted key rate over a 1 km of fiber with a mean photon number of 0.1”)
Regarding Claim 9, Ma discloses:
The quantum transmitter of Claim 1, wherein the quantum state preparation circuitry is configured to receive the sequence of bits from a random number generator. (In section 2.2, Ma discloses “The Random Number Generator module on Alice’s FPGA generates two bit-streams of pseudo random data at up to 1.25 Gbit/s; one stream for the bit value and the other for the basis.”)
Regarding Claim 10, Ma discloses:
A quantum receiver for use in quantum key distribution (QKD), the quantum receiver comprising (In section 3.1, Ma discloses “Fig. 4 shows a schematic diagram of our fiber-based BB84 QKD system, which uses a pair of our PCBs to process the data at a continuous high data rate [13] to create a shared sifted key according to the BB84 protocol.”): a quantum channel interface configured to receive (In section 2.2, Ma discloses “Each packet is then passed to the Transmit/Receive module where they are synchronously sent to Bob on the quantum channel along with a “Sync” message on the classical channel.”), via a multimode optical fiber quantum communication channel, qubits from a quantum transmitter (In section 2.2 Ma discloses “When a “Sync” message is received by the Transmit/Receive module in Bob’s FPGA, it begins the capture of one packet’s worth of data from the Quantum channels.” And in Section 6.2, Ma further discloses “SMF-28 cannot provide single mode transmission at 850 nm”); a photon detector operatively coupled to the quantum channel interface and configured to detect the qubits at an operational wavelength of around 850 nm (In section 3.5, Ma discloses “After an APD detects a photon, the avalanche process generates an electrical output signal.”), wherein the photon detector is a silicon-based single photon avalanche diode (SPAD) (In section 1, Ma discloses “For LANs, our 850 nm QKD system is a good choice, since it uses low-cost Vertical Cavity Surface Emitting Laser (VCSEL) and Silicon avalanche photon detectors (Si-APDs).”); and quantum state measurement circuitry operatively coupled to the photon detector (In section 3.1, Ma discloses “After the coupler, a polarization compensation module recovers the photon’s polarization state and a polarizing beam-splitter (PBS) separates the photons by their polarization directing them to a Si-APD (Perkin Elmer SPCM-AQR-14) [24] that feeds Bob’s PCB.”) and configured to: select measurement bases to decode states of the qubits (In section 3.1, Ma discloses “a 1 × 2 non-polarizing single-mode fiber coupler performs a random choice of polarization basis measurement.”); and decode states of the qubits based on the measurement bases (In section 2.1, Ma discloses “If Bob chooses correctly, the value he measures will be correct.”).
Regarding Claim 14, Ma discloses:
The quantum receiver of Claim 10, wherein the quantum receiver is configured to operate at a room temperature. (In section 5, Ma discloses “Si-APDs are low cost, operate at room temperature and have the highest peak detection efficiency among these detectors”)
Regarding Claim 15, Ma discloses:
The quantum receiver of Claim 10, further comprising security and protocol management circuitry configured to: transmit, to the quantum transmitter via a classical communication channel, the measurement bases used to decode the qubits (In section 2.1, Ma discloses “The next three stages of the protocol, common to both BB84 and B92, are conducted over an unsecured public link (called the classical channel, since this can be standard IP communications)… The second stage is sifting, where Bob sends a list back to Alice of photons detected and their basis (measurement state), but not their value.”).
Regarding Claim 16, Ma discloses:
The quantum receiver of Claim 15, wherein the security and protocol management circuitry is further configured to: receive, from the quantum transmitter via the classical communication channel, a measurement bases used to encode the bits (In section 2.1, Ma discloses “Bob randomly chooses to measure the photons in either the horizontal-vertical or diagonal basis… where Bob sends a list back to Alice of photons detected and their basis (measurement state), but not their value.”) and establish a shared encryption key with the quantum transmitter using bits and qubits with matching measurement bases (In section 2.1, Ma discloses “Alice and Bob now have a list of sifted keys.”).
Claim 17 is directed to a method having functionality corresponding to the system of Claim 1, and is rejected by a similar rationale, mutatis mutandis.
Claim 19 is directed to a method having functionality corresponding to the system of Claim 10, and is rejected by a similar rationale, mutatis mutandis.
Regarding Claim 21, Ma discloses:
A quantum transmitter for use in quantum key distribution (QKD) (In section 3.1, Ma discloses “Fig. 4 shows a schematic diagram of our fiber-based BB84 QKD system, which uses a pair of our PCBs to process the data at a continuous high data rate [13] to create a shared sifted key according to the BB84 protocol.”), the quantum transmitter comprising: a light source configured to generate photons at an operational wavelength of around 850 nm, wherein the light source is an on-chip semiconductor laser (In section 1, Ma discloses “For LANs, our 850 nm QKD system is a good choice, since it uses low-cost Vertical Cavity Surface Emitting Laser (VCSEL) and Silicon avalanche photon detectors (Si-APDs).” And further in section 3.1 “Each of the four outputs drives a 10 Gbit/s 850 nm VCSEL that generates a laser pulse. ”); quantum state preparation circuitry operatively coupled to the light source and configured to (In section 2.2, Ma discloses “These electrical signals are sent from the PCB to the photonics, where they are shaped and converted to optical signals for the classical channel and single photons for the quantum channels.”): receive a sequence of bits (In section 2.2, Ma discloses “The Random Number Generator module on Alice’s FPGA generates two bit-streams of pseudo random data at up to 1.25 Gbit/s each; one stream for the bit value and the other for the basis.”); map the bits to respective quantum states and measurement bases (In section 2.1, Ma discloses “In the BB84 system, each photon is set in one of the four linear polarization states: horizontal-vertical (belonging to the horizontal-vertical basis) or +/- 45 degree diagonal (belonging to the diagonal basis). One of the polarization states in each basis represents a “0” bit value and the other a “1”.”); and encode the quantum states onto respective photons based on the measurement bases to generate a corresponding qubits (In section 3.1, Ma discloses “A linear polarizer and a half-wave plate (HWP) sets the polarization orientation, −45°, +45°, 0° or 90°, that corresponds to the output path. These four output streams are combined into a single stream by non-polarizing beam-splitters (NPBSs) and then sent to Bob over the quantum channel.”); and a quantum channel interface operatively coupled to the quantum state preparation circuitry (In section 3.1, Ma discloses “After the coupler, a polarization compensation module recovers the photon’s polarization state and a polarizing beam-splitter (PBS) separates the photons by their polarization directing them to a Si-APD (Perkin Elmer SPCM-AQR-14) [24] that feeds Bob’s PCB.”) and configured to transmit the qubits to a quantum receiver via a multimode optical fiber quantum communication channel (In section 2.2, Ma discloses “Each packet is then passed to the Transmit/Receive module where they are synchronously sent to Bob on the quantum channel along with a “Sync” message on the classical channel.”), wherein a transmission distance between the quantum transmitter and the quantum receiver is less than 2 km (In section 3.5, Ma discloses “this system can provide more than 4 Mbit/s of sifted key rate over a 1 km of fiber with a mean photon number of 0.1”)
Regarding Claim 23, Ma discloses:
A quantum receiver for use in quantum key distribution (QKD) (In section 3.1, Ma discloses “Fig. 4 shows a schematic diagram of our fiber-based BB84 QKD system, which uses a pair of our PCBs to process the data at a continuous high data rate [13] to create a shared sifted key according to the BB84 protocol.”), the quantum receiver comprising: a quantum channel interface configured to receive (In section 2.2, Ma discloses “Each packet is then passed to the Transmit/Receive module where they are synchronously sent to Bob on the quantum channel along with a “Sync” message on the classical channel.”), via a multimode optical fiber quantum communication channel, qubits from a quantum transmitter (In section 2.2 Ma discloses “When a “Sync” message is received by the Transmit/Receive module in Bob’s FPGA, it begins the capture of one packet’s worth of data from the Quantum channels.” And in Section 6.2, Ma further discloses “SMF-28 cannot provide single mode transmission at 850 nm”); a photon detector operatively coupled to the quantum channel interface and configured to detect the qubits at an operational wavelength of around 850 nm (In section 3.5, Ma discloses “After an APD detects a photon, the avalanche process generates an electrical output signal.”), wherein the photon detector is a silicon-based single photon avalanche diode (SPAD) (In section 1, Ma discloses “For LANs, our 850 nm QKD system is a good choice, since it uses low-cost Vertical Cavity Surface Emitting Laser (VCSEL) and Silicon avalanche photon detectors (Si-APDs).”); and quantum state measurement circuitry operatively coupled to the photon detector and configured to: select a measurement bases to decode states of qubits (In section 3.1, Ma discloses “a 1 × 2 non-polarizing single-mode fiber coupler performs a random choice of polarization basis measurement.”)and decode the states of the qubits based on the measurement bases (In section 2.1, Ma discloses “If Bob chooses correctly, the value he measures will be correct.”).
Regarding Claim 26, Ma discloses:
The quantum transmitter of Claim 1, wherein the on-chip semiconductor laser is a vertical-cavity surface-emitting laser (VCSEL). (In section 1, Ma discloses “We have developed several technologies to integrate QKD into these network categories. For LANs, our 850 nm QKD system is a good choice, since it uses low-cost Vertical Cavity Surface Emitting Laser (VCSEL) and Silicon avalanche photon detectors (Si-APDs).”)
Regarding Claim 35, Ma discloses:
The quantum transmitter of Claim 1, wherein the on-chip semiconductor laser is configured to attenuate an output of the on-chip semiconductor laser to generate single photons at the operational wavelength of around 850 nm. (In section 3.1, Ma discloses “ The intensity of the laser pulse is then attenuated by variable optical attenuators (VOA) to the single photon level. A linear polarizer and a half-wave plate (HWP) sets the polarization orientation, −45°, +45°, 0° or 90°, that corresponds to the output path. These four output streams are combined into a single stream by non-polarizing beam-splitters (NPBSs) and then sent to Bob over the quantum channel. The mean photon number (μ) at Alice’s output is set to 0.1, therefore on average, Alice emits one photon every ten pulses.”)
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 4 is rejected under 35 U.S.C. 103 as being unpatentable Ma et al. (NPL: High Speed Quantum Key Distribution Over Optical Fiber Network System), hereinafter referred to as Ma, in view of Vest et al. (NPL: Quantum key Distribution with a Hand-Held Sender Unit), hereinafter referred to as Vest.
Regarding Claim 4, Ma discloses the limitations with respect to claim 1.
However, Ma does not explicitly disclose the small form factor of the devices.
Vest discloses:
The quantum transmitter of Claim 1, wherein the quantum transmitter has a small form factor that is less than 40 cm3 in volume. (On page 2, Vest discloses “In this work we combine these technological advances in miniaturizing all optical and electronic components for a hand-held QKD transmitter module...The assembled optical module has a size of 35 × 20 × 8 mm where the large lateral extension is mainly determined by the footprint of the electric connector and of the printed circuit board (PCB, 20 × 6 mm) onto which the VCSEL array is mounted”)
One in ordinary skill in the art of cryptography would have been motivated, before the effective filing date of the claimed invention to modify Ma’s approach by utilizing Vest’s approach of using a small form factor for the transmitter as the motivation would be to allow for a reduced footprint, lowering material and deployment costs consistent with Ma’s stated objective (See Vest, Abstract).
Claim 13 is rejected under 35 U.S.C. 103 as being unpatentable Ma et al. (NPL: High Speed Quantum Key Distribution Over Optical Fiber Network System), hereinafter referred to as Ma, in view of Nordhold et al. (US 20160065365 ), hereinafter referred to as Nordholt.
Regarding Claim 13, Ma discloses the limitations with respect to claim 10.
However, Ma does not explicitly disclose the small form factor of the devices.
Nordholt discloses:
wherein the quantum receiver has a small form factor that is less than 40 cm3 in volume. (In ¶ 93, Nordholt discloses “a QC card includes modules that implement a QC receiver,” and further in ¶ 56 “The QC card can be fabricated as a single integrated unit with a small footprint.”)
One in ordinary skill in the art of cryptography would have been motivated, before the effective filing date of the claimed invention to modify Ma’s approach by utilizing Nordholt’s approach of using a small form factor for the receiver as the motivation would be to allow for a reduced footprint, lowering material and deployment costs consistent with Ma’s stated objective (See Nordholt, ¶ 92).
Claims 25 and 27 are rejected under 35 U.S.C. 103 as being unpatentable Ma et al. (NPL: High Speed Quantum Key Distribution Over Optical Fiber Network System), hereinafter referred to as Ma, in view of Ramos et al. (NPL: Datacom-Agnostic Shortwave QKD for Short-Reach Links), hereinafter referred to as Ramos.
Regarding Claim 25, Ma discloses the limitations with respect to claim 1.
However, Ma does not explicitly disclose the use in data centers.
Ramos discloses:
The quantum transmitter of Claim 1, wherein the quantum transmitter is configured to operate in a data center environment. (In the introduction, Ramos discloses “The need for QKD is now enhanced through the rapid scale-up of datacenters, a domain originally characterized by perimeter security but currently on the migration to a zero-trust model where no resource within its short-reach networks is inherently trusted”)
One in ordinary skill in the art of cryptography would have been motivated, before the effective filing date of the claimed invention to modify Ma’s approach by utilizing Nordholt’s approach of using a small form factor for the receiver as the motivation would be to allow for a reduced footprint, lowering material and deployment costs consistent with Ma’s stated objective (See Nordholt, ¶ 92).
Regarding Claim 27, Ma discloses the limitations with respect to claim 10.
However, Ma does not explicitly disclose the use in data centers.
Ramos discloses:
The quantum receiver of Claim 10, wherein the quantum receiver is configured to operate in a data center environment. (In the introduction, Ramos discloses “we experimentally demonstrate datacom-blind QKD operation at 852 nm over a 1-km short-reach optical interconnect”)
One in ordinary skill in the art of cryptography would have been motivated, before the effective filing date of the claimed invention to modify Ma’s approach by utilizing Ramos’ approach of using the quantum key distribution system in a data center environment as the motivation would be the rapid scale up of data centers and the need for short-reach interconnects (See Ramos, Introduction).
Claims 33 and 36 are rejected under 35 U.S.C. 103 as being unpatentable Ma et al. (NPL: High Speed Quantum Key Distribution Over Optical Fiber Network System), hereinafter referred to as Ma, in view of Padullaparthi (US: 9438010), hereinafter referred to as Padullaparthi.
Regarding Claim 33, Ma discloses the limitations with respect to claim 1.
However, Ma does not explicitly disclose the use standard optical fibers.
Padullaparthi discloses:
The quantum transmitter of Claim 1, wherein the multimode optical fiber quantum communication channel comprises a standard multimode optical fiber optimized for optical communication at wavelengths around 850 nm. (In Col 5, Lines 66-67, Padullaparthi discloses “However at 850 nm band, standard OM2, OM3, OM4 fibers can readily be used for data transmission without having dispersion compensated fibers.”)
One in ordinary skill in the art of cryptography would have been motivated, before the effective filing date of the claimed invention to modify Ma’s approach by utilizing Padullaparthi’s approach of using standard multimode optical fibers as the motivation would be the ability to carry a 850 nm VSEL transmission without compensation (See Padullaparthi, Col 5-6).
Regarding Claim 36, Ma discloses the limitations with respect to claim 10.
However, Ma does not explicitly disclose the use standard optical fibers.
Padullaparthi discloses:
The quantum receiver of Claim 10, wherein the multimode optical fiber quantum communication channel comprises a standard multimode optical fiber optimized for optical communication at wavelengths around 850 nm. (In Col 5, Lines 66-67, Padullaparthi discloses “However at 850 nm band, standard OM2, OM3, OM4 fibers can readily be used for data transmission without having dispersion compensated fibers.”)
One in ordinary skill in the art of cryptography would have been motivated, before the effective filing date of the claimed invention to modify Ma’s approach by utilizing Padullaparthi’s approach of using standard multimode optical fibers as the motivation would be the ability to carry a 850 nm VSEL transmission without compensation (See Padullaparthi, Col 5-6).
Claims 34 and 37 are rejected under 35 U.S.C. 103 as being unpatentable Ma et al. (NPL: High Speed Quantum Key Distribution Over Optical Fiber Network System), hereinafter referred to as Ma, in view of Rhee et al. (US 20200195428), hereinafter referred to as Rhee.
Regarding Claim 34, Ma discloses the limitations with respect to claim 1.
However, Ma does not explicitly disclose the use of a quantum memory.
Rhee discloses:
The quantum transmitter of Claim 1, wherein the quantum state preparation circuitry comprises a quantum memory configured to: store quantum information represented by the quantum states; and synchronize generation of the quantum states with encoding of the quantum states onto the photons by holding the quantum states until the quantum states are encoded onto the photons. (In ¶ 40, Rhee discloses “The quantum memory 112 stores the remaining entangled quantum state other than a part (B.sub.0) of the entangled quantum state split and output from the beam splitter (S21).” And further discloses in ¶ 45 “For example, when a plurality of entangled quantum states for the coded cryptographic key transmitted from the transmitter (Alice) is stored in the quantum memory 121,”)
One in ordinary skill in the art of cryptography would have been motivated, before the effective filing date of the claimed invention to modify Ma’s approach by utilizing Rhee’s approach of using a quantum memory as the motivation would be that a quantum memory incorporated with a transmitter and receiver would allow a buffer of the states and synchronization. (See Rhee, ¶ 43).
Regarding Claim 37, Ma discloses the limitations with respect to claim 10.
However, Ma does not explicitly disclose the use of a quantum memory.
Rhee discloses:
The quantum receiver of Claim 10, wherein the quantum state measurement circuitry comprises a quantum memory configured to: temporarily store quantum information associated with the qubits prior to completion of the decoding of the states of the qubits; and synchronize reception of the qubits with selection and application of the measurement bases used to decode the states of the qubits. (In ¶ 43, Rhee discloses “stores a part (B.sub.0) of the entangled quantum state received from the transmitter (Alice) through the quantum channel and outputs the part (B.sub.0) by delaying a predetermined time (S30). The entangled quantum state output from the quantum memory 121 will be marked with B.”)
One in ordinary skill in the art of cryptography would have been motivated, before the effective filing date of the claimed invention to modify Ma’s approach by utilizing Rhee’s approach of using a quantum memory as the motivation would be that a quantum memory incorporated with a transmitter and receiver would allow a buffer of the states and synchronization. (See Rhee, ¶ 43).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Bertrand et al. (US 20260074800) discloses a method for quantum key distribution and encoding of signals.
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/SHADI H KOBROSLI/Examiner, Art Unit 2492 /RUPAL DHARIA/Supervisory Patent Examiner, Art Unit 2492
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