Search

CN-121995657-A - Programmable optical frequency comb light source based on chromatic dispersion reconfigurable microcavity

CN121995657ACN 121995657 ACN121995657 ACN 121995657ACN-121995657-A

Abstract

The invention discloses a programmable optical frequency comb light source based on a chromatic dispersion reconfigurable microcavity, which structurally comprises a grating writing and chromatic dispersion detection module, an integrated microcavity module with photorefractive characteristics, an optical comb pumping and spectrum sensing module and a feedback control and signal processing module, wherein the working principle is that a Bragg grating capable of being programmed is written on a micro-ring resonant cavity with the photorefractive effect by utilizing laser so as to reconstruct the chromatic dispersion curve of the microcavity in real time; then, by monitoring the spectrum and the repetition frequency of the output optical comb and comparing the spectrum with a target set by a user, an intelligent feedback closed loop is formed, and the grating pattern is automatically adjusted until the output spectrum is matched with the target. The programmable optical frequency comb light source can be dynamically reconstructed or switched according to different application requirements. The programmable optical frequency comb can be used as a light source module of a co-packaging optical technology, bandwidth density is improved, power consumption is reduced, and therefore wide application in interconnection of next-generation data centers is achieved.

Inventors

  • ZHANG BIN
  • XIA DI

Assignees

  • 中山大学

Dates

Publication Date
20260508
Application Date
20260203

Claims (7)

  1. 1. A dispersion reconfigurable microcavity-based programmable optical frequency comb light source, comprising: An integrated microcavity module with photorefractive properties, the refractive index profile inside of which is non-volatile modulated by an external optical field; The grating writing and dispersion detection module is used for performing dispersion programming and characterization on the integrated microcavity module; the optical comb pumping and spectrum sensing module is used for exciting the optical comb and monitoring the output characteristic of the optical comb; And the feedback control and signal processing module is used for responding to the user input, receiving the data from the grating writing and dispersion detection module and the data of the optical comb pumping and spectrum sensing module and regulating and controlling the programmable optical frequency comb light source.
  2. 2. The programmable optical frequency comb light source based on a chromatic dispersion reconfigurable microcavity of claim 1, wherein the grating writing and chromatic dispersion detection module specifically comprises: A write gate laser and a tunable laser; The first optical switch is used for switching the input end write gate laser and the detection laser; the second optical switch is used for switching the output end; A power meter for detecting an output power; And the data acquisition device is used for acquiring the microcavity transmission spectrum line.
  3. 3. The programmable optical frequency comb light source based on the chromatic dispersion reconfigurable microcavity according to claim 2, wherein the grating writing and chromatic dispersion detection module works as follows: Switching a light source selectively injected into the microcavity through the first optical switch; guiding microcavity output to a corresponding detector through the switching of the second optical switch; when the first optical switch is switched to the write grating laser and the second optical switch is switched to the power timing, the system enters a grating writing and erasing mode, and the feedback control and signal processing module adjusts the frequency of the write grating laser to finish accurate writing or erasing of the grating; When the first optical switch is switched to the tunable laser and the second optical switch is switched to the data collector, the system enters a dispersion test mode, and real-time dispersion distribution of the microcavity is obtained by scanning and detecting laser wavelength and recording transmission spectrum and analyzing by the feedback control and signal processing module.
  4. 4. The dispersion reconfigurable microcavity based programmable optical frequency comb light source of claim 1 wherein the microcavity of the integrated microcavity module having photorefractive properties is fabricated from any one of, but not limited to, arsenic sulfide, arsenic selenide, arsenic selenium germanium, arsenic sulfide, selenium tellurium germanium, sulfur arsenic sulfide selenium, lithium niobate, lithium tantalate.
  5. 5. The dispersion reconfigurable microcavity based programmable optical frequency comb light source of claim 1 wherein the optical comb pump and spectral sensing module includes a pump laser at the input and an optical coupler at the output, the output of the optical comb pump and spectral sensing module including two parts, wherein: part of output is input into a spectrum analyzer, and the shape of the spectrum of the output optical comb is tested; The other part of the output is used for testing the repetition frequency of the optical comb.
  6. 6. The programmable optical frequency comb light source based on a chromatic dispersion reconfigurable microcavity according to claim 1, wherein the working process of the feedback control and signal processing module is specifically as follows: receiving a target spectrum from a user input; Acquiring an actual spectrum monitored by a spectrum sensing module in real time, and calculating the difference between the actual spectrum and the target spectrum; Finding comb teeth with the consistency exceeding a set value according to the difference, retesting microcavity dispersion, and calculating grating writing mode splitting quantity required by compensating the difference to obtain grating writing control parameters; And issuing the grating writing control parameters to the grating writing and dispersion detection module to execute dispersion reconstruction.
  7. 7. The dispersion reconfigurable microcavity based programmable optical frequency comb light source of claim 6 further comprising: A cyclic difference calculating step, a control parameter calculating step and a chromatic dispersion reconstructing step, and locking output when the difference is smaller than a set threshold value.

Description

Programmable optical frequency comb light source based on chromatic dispersion reconfigurable microcavity Technical Field The invention relates to the field of photonic integrated devices, in particular to a programmable optical frequency comb light source based on a chromatic dispersion reconfigurable microcavity. Background With the explosive growth of AI computing power demands, traditional pluggable optical modules face bottlenecks in bandwidth, power consumption, density and the like. The co-packaged optical (CPO) technology shortens the electrical interconnection distance, improves the bandwidth density and reduces the power consumption by co-packaging the optical engine and the chip, and becomes a key technology for interconnection of the next generation data center. However, existing CPO schemes rely on laser arrays, presenting wavelength number, stability and accuracy expansion challenges. Chip-scale multi-wavelength lasers are potential solutions to these problems because they can produce multiple uniformly spaced and phase-locked wavelengths from a single device. Currently, the main technical routes for realizing on-chip multi-wavelength light sources include Distributed Feedback (DFB) laser arrays, quantum dot mode-locked lasers, and the like. However, the DFB laser array has problems of poor stability of wavelength interval and inconsistent noise characteristics of each channel, and the quantum dot mode-locked laser can provide stable frequency interval, but the phase noise is generally high, and it is difficult to obtain extremely narrow line width. The Kerr optical frequency comb (microcavity optical comb) technology based on an optical microcavity generates a plurality of comb teeth which are broadband, equally spaced and phase coherent in a nonlinear micro resonant cavity through a single pump light source, has the obvious advantages of high integration, extremely stable wavelength (frequency) interval and narrow single comb tooth line width, and is regarded as a next-generation integrated multi-wavelength light source solution with great development potential. One fundamental bottleneck faced by the existing microcavity optical combing technology is that the dispersion characteristic of the core is solidified after the device design and preparation are completed, which directly results in single function, locked performance and lack of intelligent adaptability of the device. Specifically, a prepared microcavity can only support one spectrum form and cannot be dynamically reconstructed or switched according to different application requirements, the final performance of the microcavity is determined after the device is prepared, and the microcavity lacks effective post-correction and optimization capability under the condition of performance degradation or deviation from an optimal value caused by process deviation or environmental disturbance. Disclosure of Invention In order to solve the technical problem that the existing microcavity optical comb can only support one spectrum form after preparation is finished, and further, cannot be dynamically reconstructed or switched according to different application requirements, the invention provides a chromatic dispersion reconfigurable microcavity-based programmable optical frequency comb light source, which structurally comprises a grating writing and chromatic dispersion detection module, an integrated microcavity module with a photorefractive characteristic, an optical comb pumping and spectrum sensing module, a feedback control and signal processing module, and the working principle of the optical comb light source is that a laser is used for writing a programmable Bragg grating on a micro-ring resonant cavity with a photorefractive effect, so that the chromatic dispersion curve of the microcavity is reconstructed in real time; then, by monitoring the spectrum and the repetition frequency of the output optical comb and comparing the spectrum with a target set by a user, an intelligent feedback closed loop is formed, and the grating pattern is automatically adjusted until the output spectrum is matched with the target. Based on the scheme, the invention provides a programmable optical frequency comb light source based on a chromatic dispersion reconfigurable microcavity, which has the beneficial effects that 1) the function is flexible and reconfigurable, the traditional paradigm of one device one function is broken through, and the capability of self-defining spectrum is realized on an integrated optical comb. A user can dynamically switch the same device among soliton combs, flat combs and even any custom spectrum forms through instructions, so that a single chip can adaptively cover various application scenes such as communication, metering, spectroscopy and the like, and the universality and the system integration level of the device are greatly improved. 2) The manufacturing value is improved, the model innovation is promoted, the post