# US 2021/0278743 A1 · System and method for programmable nonlinear silicon photonic circuit > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0278743 A1 - Document ID: US20210278743A1 - Status: Published application - Kind: A1 - Application number: 16/775,746 - Filed: 2020-01-29 - Published: 2021-09-09 - Earliest claimed: 2019-01-30 - Assignees: The Trustees of Princeton University - Applicants: The Trustees of Princeton University - Inventors: Chaoran Huang; Thomas Ferreira De Lima; Alexander Tait; Siamak Abbaslou; Aashu Jha; Bhavin Shastri; Paul R. Prucnal; Mitchell A. Nahmias; Hsuan-Tung Peng - Web page: https://patentgrep.com/patent/US20210278743A1 ## CPC - G02F 1/225: in an optical waveguide structure - G02F 1/3517: {using an interferometer} - G02F 1/0123: {Circuits for the control or stabilisation of the bias voltage, e.g. automatic bias control [ABC] feedback loops} - G02F 1/365: in an optical waveguide structure (G02F1/377, {G02F1/395} take precedence) - G02F 2203/15: involving resonance effects, e.g. resonantly enhanced interaction - G02F: OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS ## Abstract According to various embodiments, an all-optical thresholder device is disclosed. The all-optical thresholder device includes a Mach-Zehnder interferometer (MZI) coupled to a Mach-Zehnder coupler (MZC). The MZI includes at least one microring resonator (MRR) and a first tunable element, where the MRR further includes a second tunable element. The MZC includes a third tunable element. The first, second, and third tunable elements are configured to control biases of the all-optical thresholder device to achieve a desired power transfer function. ## Claims ### Claim 1 An all-optical thresholder device, comprising: a Mach-Zehnder interferometer (MZI) coupled to a Mach-Zehnder coupler (MZC); the MZI comprising at least one microring resonator (MRR) and a first tunable element, the MRR further comprising a second tunable element; the MZC comprising a third tunable element; the first, second, and third tunable elements configured to control biases of the all-optical thresholder device to achieve a desired power transfer function. ### Claim 2 (depends on 1) The all-optical thresholder device of claim 1, further comprising an input coupled to the MZC and an output coupled to the MZI. ### Claim 3 (depends on 1) The all-optical thresholder device of claim 1, wherein the first, second, and third tunable elements each comprise one of a microheater, an electro-optical system, and a micro-electro-mechanical system. ### Claim 4 (depends on 1) The all-optical thresholder device of claim 1, wherein the first, second, and third tunable elements are controlled by an automated control system. ### Claim 5 (depends on 1) The all-optical thresholder device of claim 1, wherein the MRR is included in one of two arms of the MZI. ### Claim 6 (depends on 5) The all-optical thresholder device of claim 5, wherein a second MRR is included in the other of the two arms of the MZI. ### Claim 7 (depends on 1) The all-optical thresholder device of claim 1, wherein the third tunable element is configured to adjust a bias of the MZC to balance amplitudes of two arms of the MZI. ### Claim 8 (depends on 1) The all-optical thresholder device of claim 1, wherein the first tunable element is configured to adjust a bias of the MZI to introduce about a π phase difference. ### Claim 9 (depends on 1) The all-optical thresholder device of claim 1, wherein the second tunable element is configured to adjust a bias of the MRR such that the all-optical thresholder device is functioning at about a resonance wavelength. ### Claim 10 (depends on 1) The all-optical thresholder device of claim 1, wherein the MZI and MZC are implemented on a silicon-on-insulator (SOI) platform. ### Claim 11 (depends on 1) The all-optical thresholder device of claim 1, wherein the power transfer function is determined based on one or more nonlinear effects. ### Claim 12 (depends on 11) The all-optical thresholder device of claim 11, wherein the non-linear effects comprise one or more of a Kerr effect, two-photon absorption (TPA), TPA induced free-carrier absorption (FCA), and free-carrier dispersion (FCD). ### Claim 13 (depends on 1) The all-optical thresholder device of claim 1, wherein the first, second, and third tunable elements are controlled to maximize a slope of the power transfer function. ### Claim 14 An all-optical device, comprising: a Mach-Zehnder interferometer (MZI) coupled to a Mach-Zehnder coupler (MZC); the MZI comprising at least one microring resonator (MRR) and a first tunable element, the MRR further comprising a second tunable element; the MZC comprising a third tunable element; the first, second, and third tunable elements configured to control biases of the all-optical device to achieve a desired power transfer function. ### Claim 15 (depends on 14) The all-optical device of claim 14, further comprising an input coupled to the MZC and an output coupled to the MZI. ### Claim 16 (depends on 14) The all-optical device of claim 14, wherein the first, second, and third tunable elements each comprise one of a microheater, an electro-optical system, and a micro-electro-mechanical system. ### Claim 17 (depends on 14) The all-optical device of claim 14, wherein the first, second, and third tunable elements are controlled by an automated control system. ### Claim 18 (depends on 14) The all-optical device of claim 14, wherein the MRR is included in one of two arms of the MZI. ### Claim 19 (depends on 18) The all-optical device of claim 18, wherein a second MRR is included in the other of the two arms of the MZI. ### Claim 20 (depends on 14) The all-optical device of claim 14, wherein the third tunable element is configured to adjust a bias of the MZC to balance amplitudes of the two arms of the MZI. ### Claim 21 (depends on 14) The all-optical device of claim 14, wherein the first tunable element is configured to adjust a bias of the MZI to introduce a desired phase difference. ### Claim 22 (depends on 14) The all-optical device of claim 14, wherein the second tunable element is configured to adjust a bias of the MRR such that the all-optical device is functioning near a resonance wavelength. ### Claim 23 (depends on 14) The all-optical device of claim 14, wherein the MZI and MZC are implemented on a silicon-on-insulator (SOI) platform. ### Claim 24 (depends on 14) The all-optical device of claim 14, wherein the power transfer function is determined based on one or more nonlinear effects. ### Claim 25 (depends on 24) The all-optical device of claim 24, wherein the nonlinear effects comprise one or more of a Kerr effect, two-photon absorption (TPA), TPA induced free-carrier absorption (FCA), and free-carrier dispersion (FCD). ### Claim 26 (depends on 14) The all-optical device of claim 14, wherein the first, second, and third tunable elements are controlled to optimize the power transfer function. ### Claim 27 (depends on 14) The all-optical device of claim 14, wherein the first, second, and third tunable elements are controlled to convert a long-pulse signal into a short-pulse signal. ### Claim 28 A method for operating an all-optical device, the all-optical device including a Mach-Zehnder interferometer (MZI) coupled to a Mach-Zehnder coupler (MZC), the MZI including a first tunable element and at least one microring resonator (MRR) having a second tunable element, the MZC having a third tunable element, the method comprising: controlling the first tunable element to adjust a bias of the MZI to introduce a desired phase difference; controlling the second tunable element to adjust a bias of the MRR such that the all-optical device is functioning at about a resonance wavelength; and controlling the third tunable element to adjust a bias of the MZC to balance amplitudes of two arms of the MZI; the biases of the MZI, MRR, and MZC being controlled to achieve a desired power transfer function. ### Claim 29 (depends on 28) The method of claim 28, wherein the first, second, and third tunable elements each comprise one of a microheater, an electro-optical system, and a micro-electro-mechanical system. ### Claim 30 (depends on 28) The method of claim 28, further comprising controlling the first, second, and third tunable elements by an automated control system. ### Claim 31 (depends on 28) The method of claim 28, wherein the MZI and MZC are implemented on a silicon-on-insulator (SOI) platform.