# US 2014/0153720 A1 · Quantum key distribution (qsd) scheme using photonic integrated circuit (pic) > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0153720 A1 - Document ID: US20140153720A1 - Status: Published application - Kind: A1 - Application number: 13/705,720 - Filed: 2012-12-05 - Published: 2014-06-05 - Earliest claimed: 2012-12-05 - Assignees: Intel Corporation - Inventors: Christopher J. Jezewski; Kelin J. Kuhn; Marko Radosavljevic - Web page: https://patentgrep.com/patent/US20140153720A1 ## CPC - H04L 9/0852: {Quantum cryptography (transmission systems employing electromagnetic waves other than radio waves, e.g. light, infrared H04B10/00; wavelength-division multiplex systems H04J14/02; WDM arrangements H04J14/03)} - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract Described herein are techniques related to implementation of a quantum key distribution (QKD) scheme by a photonic integrated circuit (PIC). For example, the PIC is a component in a wireless device that is used for quantum communications in a quantum communications system. ## Claims ### Claim 1 A photonic integrated circuit (PIC) that utilizes a quantum key distribution (QSD) scheme comprising: a hybrid silicon laser that is configured to produce light signals; a polarizer that receives the light signals, the polarizer is configured to change polarization of the light signals into a beam that includes a well-defined polarization; a modulator coupled to the laser array, the modulator modulates the beam for transmission through a quantum channel. ### Claim 2 (depends on 1) A PIC as recited in claim 1, wherein the hybrid silicon laser utilizes a III-V based laser. ### Claim 3 (depends on 1) A PIC as recited in claim 1, wherein the light signals include at least one photon that is configured to be a carrier of information. ### Claim 4 (depends on 1) A PIC as recited in claim 1, wherein the hybrid silicon laser utilizes a corrugated grating that is configured to transfer the light signals with different wavelengths from the hybrid silicon laser to the modulator. ### Claim 4 (depends on 1) A PIC as recited in claim 1, wherein the polarizer is set to the same setting as another polarizer of a receiver system in a quantum communications system. ### Claim 5 (depends on 1) A PIC as recited in claim 1, wherein the polarizer utilizes a beam splitter that is configured to split the light signal into different polarization. ### Claim 6 (depends on 1) A PIC as recited in claim 1, wherein the modulator is configured to utilize a phase modulation or polarization modulation of the beam to transmit qubits in the quantum channel. ### Claim 7 (depends on 1) A PIC as recited in claim 1, wherein the modulator is set to the same setting with a demodulator of a receiver system in a quantum communications system. ### Claim 8 (depends on 1) A PIC as recited in claim 1 further comprising a photo detector that is configured to measure received light signals when the PIC is at receive mode, wherein the photo detector utilizes a corrugated grating in receiving the light signals. ### Claim 9 (depends on 1) A wireless device comprising a PIC as recited in claim 1. ### Claim 10 A wireless device that utilizes a quantum key distribution (QSD) scheme comprising: a photonic integrated circuit (PIC) that includes: a laser array that is configured to produce light signals; a polarizer that receives the light signals; a modulator coupled to the laser array, the modulator modulates the polarized light signals for transmission in a quantum channel; a processor configured to the PIC. ### Claim 11 (depends on 10) A wireless device as recited in claim 10, wherein the laser array is a hybrid silicon layer that utilizes a Si laser or III-V based lasers. ### Claim 12 (depends on 10) A wireless device as recited in claim 10, wherein the hybrid silicon laser utilizes a corrugated grating that is configured to transfer the light signals with different wavelengths from the hybrid silicon laser to the modulator. ### Claim 13 (depends on 10) A wireless device as recited in claim 10, wherein the polarizer is set to the same setting as another polarizer of a receiver system in a quantum communications system. ### Claim 14 (depends on 10) A wireless device as recited in claim 10, wherein the polarizer is configured to change polarization of the light signals into a beam that includes a well-defined polarization. ### Claim 15 (depends on 10) A wireless device as recited in claim 10, wherein the polarizer utilizes a beam splitter to split the light signal into differing polarization. ### Claim 16 (depends on 10) A wireless device as recited in claim 10, wherein the modulator is configured to utilize a phase modulation or polarization modulation of the polarized light signals to transmit qubits in the quantum channel. ### Claim 17 (depends on 10) A wireless device as recited in claim 10, wherein the modulator is set to the same setting with a demodulator of a receiver system in a quantum communications system. ### Claim 18 (depends on 10) A wireless device as recited in claim 10 further comprising a photo detector that is configured to measure received light signals when the PIC is at receive mode, wherein the photo detector utilizes a corrugated grating in receiving the light signals. ### Claim 19 A method for fabricating a photonic integrated circuit (PIC) that utilizes a quantum key distribution (QSD) scheme comprising: building a hybrid silicon laser array that is configured to produce light signals; building a polarizer that is configured to receive and change polarization of the light signals; building a modulator that is coupled to the hybrid silicon laser array, the modulator modulates the polarized light signals for transmission in a quantum channel. ### Claim 20 (depends on 19) A method as recited in claim 19, wherein the laser array is a hybrid silicon layer that utilizes a Si laser or III-V based lasers. ### Claim 21 (depends on 19) A method as recited in claim 19, wherein the hybrid silicon laser utilizes a corrugated grating that is configured to transfer the light signals with different wavelengths from the hybrid silicon laser to the modulator. ### Claim 22 (depends on 19) A method as recited in claim 19, wherein the polarizer is set to the same setting as another polarizer of a receiver system in a quantum communications system. ### Claim 23 (depends on 19) A method as recited in claim 19, wherein the polarizer is configured to change polarization of the light signals into a beam that includes a well-defined polarization ### Claim 24 (depends on 19) A method as recited in claim 19, wherein the polarizer utilizes a beam splitter to split the light signal into differing polarization. ### Claim 25 (depends on 19) A method as recited in claim 19, wherein the modulator uses a phase modulation or polarization modulation of the polarized light signals to transmit qubits in the quantum channel. ### Claim 26 (depends on 19) A method as recited in claim 19, wherein the modulator is set to the same setting with a demodulator of a receiver system in a quantum communications system. ### Claim 27 (depends on 19) A method as recited in claim 19 further comprising building a photo detector that is configured to measure received light signals when the PIC is at receive mode, wherein the photo detector utilizes a corrugated grating in receiving the light signals.