PHOTONICS PROCESSOR ARCHITECTURE
Photonic processors are described. The photonic processors described herein are configured to perform matrix multiplications (e.g., matrix vector multiplications). Matrix multiplications are broken down in scalar multiplications and scalar additions. Some embodiments relate to devices for performing scalar additions in the optical domain. One optical adder, for example, includes an interferometer having a plurality of phase shifters and a coherent detector. Leveraging the high-speed characteristics of these optical adders, some processors are sufficiently fast to support clocks in the tens of gigahertz of frequency, which represent a significant improvement over conventional electronic processors.
1 . An integrated photonics system comprising:
a vertical cavity surface emitting laser (VCSEL); and
a photonic integrated circuit (PIC) comprising a photonic processor configured to perform matrix multiplication, wherein the VCSEL is optically coupled to the photonic processor.
2 . The integrated photonics system of claim 1 , wherein:
the VCSEL is configured to generate light having a center wavelength less than 1.1 μm, and
the PIC further comprises a waveguide optically coupling the VCSEL to the photonic processor, the waveguide being transparent to the center wavelength.
3 . The integrated photonics system of claim 2 , wherein the VCSEL is directly modulatable.
4 . The integrated photonics system of claim 2 , further comprising an optical signal monitor configured to monitor an intensity of the light generated by the VCSEL.
5 . The integrated photonics system of claim 2 , wherein the VCSEL is a first VCSEL, the waveguide is a first waveguide, the center wavelength is a first center wavelength and the photonics system further comprises:
a second VCSEL configured to generate light having a second center wavelength less than 1.1 μm; and
a second waveguide optically coupling the second VCSEL to the photonic processor, the second waveguide being transparent to the second center wavelength.
6 . The integrated photonics system of claim 5 , wherein the first center wavelength differs from the second center wavelength.
7 . The integrated photonics system of claim 2 , wherein the photonic processor comprises a plurality of modulatable detectors, wherein the photonic processor is configured to perform matrix multiplication at least in part using the plurality of modulatable detectors.
8 . The integrated photonics system of claim 2 , wherein the PIC comprises a silicon substrate, and the waveguide comprises silicon nitride.
9 . The integrated photonics system of claim 2 , wherein the waveguide is optically coupled to the VCSEL at least in part by an out-of-plane optical coupler.
10 . A method of operating an integrated photonics system to perform matrix multiplication, the method comprising:
coupling light to a photonic processor of a photonic integrated circuit (PIC), wherein the coupling comprises:
generating the light with a vertical cavity surface emitting laser (VCSEL); and
coupling the light generated by the VCSEL to the photonic processor using a waveguide of the PIC; and
using the light to perform matrix multiplication.
11 . The method of claim 10 , wherein generating the light with the VCSEL comprises generating light having a center wavelength less than 1.1 μm, and wherein coupling the light generated by the VCSEL to the photonic processor using the waveguide of the PIC comprises using a waveguide being transparent to the center wavelength.
12 . The method of claim 10 , wherein using the light to perform matrix multiplication comprises modulating the light using a plurality of modulatable detectors.
13 . The method of claim 10 , wherein generating the light with the VCSEL comprises directly modulating the VCSEL.
14 . The method of claim 10 , further comprising monitoring an intensity of the light generated by the VCSEL.
15 . The method of claim 14 , wherein generating the light with the VCSEL further comprises generating a feedback signal based on the actual intensity of the light generated by the VCSEL.
16 . The method of claim 10 , wherein generating the light with the VCSEL comprises generating light having a first center wavelength, and wherein coupling the light to the photonic processor further comprises:
generating the light with a second VCSEL, the second VCSEL configured to generate light having a second center wavelength less than 1.1 μm;
coupling the light generated by the second VCSEL to the photonic processor using a second waveguide of the PIC, the waveguide being transparent to the center wavelength of the light generated by the second VCSEL.
17 . The method of claim 16 , wherein generating light having a second center wavelength comprises generating light having a different center wavelength than the first center wavelength.
18 . A method of manufacturing an integrated photonics system, comprising:
obtaining a substrate comprising a vertical cavity surface emitting laser (VCSEL) configured to generate light having a center wavelength less than 1.1 μm;
obtaining a photonic integrated circuit (PIC) comprising:
a photonic processor configured to perform matrix multiplication; and
a waveguide optically coupled to the photonic processor, the waveguide being transparent to the center wavelength; and
bonding the VCSEL to the PIC so that the waveguide optically couples the VCSEL to the photonic processor.
19 . The method of manufacturing of claim 18 , wherein bonding the VCSEL to the PIC comprises flip-chip bonding the substrate comprising the VCSEL to the PIC.
20 . The method of manufacturing of claim 18 , wherein the PIC is formed on a silicon substrate and the waveguide is formed of silicon nitride.