CN-121978797-A - Silicon optical chip, external cavity laser and method for inhibiting micro-ring nonlinear effect

CN121978797ACN 121978797 ACN121978797 ACN 121978797ACN-121978797-A

Abstract

The invention relates to the technical field of optical communication, in particular to a silicon optical chip, an external cavity laser and a method for inhibiting micro-ring nonlinear effect, wherein the silicon optical chip, the external cavity laser and the method are connected with external input voltage and ground through an electric connection module; on the other hand, the P doped region and the N doped region are respectively connected with external input voltage and ground through the electric connection module, so that bias control on two sides of the micro-ring resonant waveguide can be realized on the basis of not increasing redundant pins, free carriers generated in the micro-ring resonant cavity are eliminated, and further, the nonlinear effect of the micro-ring resonant cavity is effectively restrained, and the micro-ring resonant cavity has the advantages of being simple in structure and meeting the miniaturization requirement.

Inventors

ZHAO XIANMENG
HU LEILEI
CHEN HONGGANG
ZHANG BO
LUO YONG

Assignees

武汉光迅科技股份有限公司

Dates

Publication Date: 20260505
Application Date: 20260105

Claims (10)

1. The silicon optical chip is characterized by comprising an electric connection module, a micro-ring resonance waveguide and an optical reflection module, wherein the micro-ring resonance waveguide is coupled with the optical reflection module; the micro-ring resonance waveguide is used for receiving an external first optical signal and carrying out wavelength selection on the first optical signal to obtain a second optical signal; The electric connection module is used for being connected with external input voltage and ground respectively; The micro-ring resonance waveguide comprises an electric connection module, wherein a P doped region and an N doped region are respectively arranged on two sides of the micro-ring resonance waveguide, and the N doped region and the P doped region are respectively connected with the electric connection module; The N doped region is connected with an external input voltage through the electric connection module, the P doped region is grounded through the electric connection module, so that a transverse electric field is constructed in the micro-ring resonance waveguide, and free carriers generated by the micro-ring resonance waveguide after light passing are removed through the transverse electric field.
2. The silicon optical chip of claim 1, further comprising a heating module coupled to the electrical connection module, the heating module disposed adjacent to the micro-ring resonator waveguide, the heating module configured to adjust a phase of an optical signal in the micro-ring resonator waveguide by heating.
3. The silicon optical chip of claim 1, further comprising a detection module coupled to the electrical connection module, the detection module coupled to the micro-ring resonant waveguide for monitoring the intensity of the optical signal in the micro-ring resonant waveguide.
4. The silicon optical chip of claim 3, wherein the detection module comprises a photodiode, a transimpedance amplifier, and a feedback resistor, the photodiode being coupled with the micro-ring resonant waveguide; The positive input end of the transimpedance amplifier is connected with the electric connection module and is used for being connected with input voltage through the electric connection module; the anode of the photodiode is connected with the inverting input end of the transimpedance amplifier so as to be connected with input voltage through the electric connection module; The cathode of the photodiode is connected with the electric connection module and is used for being connected with input voltage through the electric connection module; one end of the feedback resistor is connected with the output end of the transimpedance amplifier, and the other end of the feedback resistor is connected with the inverting input end of the transimpedance amplifier; and the output end of the transimpedance amplifier is connected with the electric connection module so as to be connected with an external electric control module through the electric connection module.
5. The silicon optical chip of claim 1, further comprising a mode spot-size converter coupled to an input of the micro-ring resonator waveguide, the mode spot-size converter configured to reduce loss of the first optical signal into the micro-ring resonator waveguide.
6. The silicon optical chip of claim 1, wherein the micro-ring resonator waveguide comprises at least two cascaded micro-ring resonators, and the radii of the two micro-ring resonators differ by a predetermined dimension.
7. An external cavity laser, comprising a gain chip, an electrical control module, and a silicon photochip according to any one of claims 1-6; The electric control module is respectively connected with the electric connection module in the silicon optical chip and the control end of the gain chip, and the gain chip is coupled with the input end of the micro-ring resonance waveguide; The gain chip is used for sending out the first optical signal under the drive of the electrical control module and transmitting the first optical signal to the micro-ring resonant waveguide; the gain chip is also used for receiving a second optical signal from the micro-ring resonant waveguide to serve as an output optical signal of the external cavity laser.
8. The external cavity laser of claim 7, wherein an anti-reflection film is coated on a coupling surface of the gain chip and the silicon optical chip, and a reflection film is coated on the other surface of the gain chip.
9. A method for suppressing the nonlinear effect of a micro-ring, which is applied to the silicon optical chip as claimed in any one of claims 1 to 6, comprising: the N doped region is connected with external input voltage through the electric connection module, and the P doped region is grounded through the electric connection module so as to construct a transverse electric field in the micro-ring resonance waveguide; And removing free carriers generated by the micro-ring resonance waveguide after light passing through the transverse electric field.
10. The method of suppressing a micro-ring nonlinear effect according to claim 9, further comprising varying the intensity of a lateral electric field in said micro-ring resonator waveguide by varying an input voltage applied to said N-doped region to control the removal rate of free carriers in said micro-ring resonator waveguide.

Description

Silicon optical chip, external cavity laser and method for inhibiting micro-ring nonlinear effect Technical Field The invention relates to the technical field of optical communication, in particular to a silicon optical chip, an external cavity laser and a method for inhibiting micro-ring nonlinear effect. Background Digital coherent optical communication is considered as a development direction of the next generation optical communication system due to its potential to realize large capacity and long distance transmission. Pushing the capacity of the optical fiber to 100 Gbs/wavelength or higher, the number of deployments of coherent optical systems is increasing with the increase of the capacity of the optical fiber. A coherent tunable laser is an important and advantageous element of such a network. In order for a coherent tunable laser to meet the emerging needs and the upcoming needs of a coherent system, a coherent tunable laser is required to have as large an adjustment range of laser wavelength, as narrow a linewidth, a low size, and low power consumption performance as possible. In order to achieve the above object, a silicon-based external cavity tunable laser (External Cavity Tunable Laser, abbreviated ECL) based on a micro-ring resonator has been developed. However, due to the power enhancement effect of the micro-ring resonator and the strong two-photon absorption effect of the silicon waveguide, ECL output power and linewidth index can be significantly affected. In most cases, the two-photon absorption effect of silicon generates free carriers and holes when the micro-ring cavity is injected with high power laser light. If free carriers cannot be removed from the waveguide in time, the carrier dispersion effect, carrier absorption effect and random recombination of free carriers and holes of silicon can generate thermal effects, which can influence the resonance wavelength of the micro-ring and can cause oscillation of the resonance wavelength of the micro-ring under certain conditions. In view of this, overcoming the drawbacks of the prior art is a problem to be solved in the art. Disclosure of Invention The invention aims to solve the technical problem of eliminating free carriers generated in a micro-ring resonant cavity, thereby effectively inhibiting the nonlinear effect of the micro-ring resonant cavity. The invention adopts the following technical scheme: In a first aspect, a silicon optical chip is provided, comprising an electrical connection module, a micro-ring resonance waveguide and an optical reflection module, wherein the micro-ring resonance waveguide is coupled with the optical reflection module; the micro-ring resonance waveguide is used for receiving an external first optical signal and carrying out wavelength selection on the first optical signal to obtain a second optical signal; The electric connection module is used for being connected with external input voltage and ground respectively; The micro-ring resonance waveguide comprises an electric connection module, wherein a P doped region and an N doped region are respectively arranged on two sides of the micro-ring resonance waveguide, and the N doped region and the P doped region are respectively connected with the electric connection module; The N doped region is connected with an external input voltage through the electric connection module, the P doped region is grounded through the electric connection module, so that a transverse electric field is constructed in the micro-ring resonance waveguide, and free carriers generated by the micro-ring resonance waveguide after light passing are removed through the transverse electric field. Preferably, the micro-ring resonant waveguide comprises an electric connection module, a heating module and a control module, wherein the electric connection module is connected with the electric connection module, the heating module is arranged adjacent to the micro-ring resonant waveguide and is used for adjusting the phase of an optical signal in the micro-ring resonant waveguide through heating. Preferably, the micro-ring resonator further comprises a detection module, wherein the detection module is connected with the electrical connection module, and the detection module is coupled with the micro-ring resonator waveguide and used for monitoring the intensity of an optical signal in the micro-ring resonator waveguide. Preferably, the detection module comprises a photodiode, a transimpedance amplifier and a feedback resistor, wherein the photodiode is coupled with the micro-ring resonance waveguide; The positive input end of the transimpedance amplifier is connected with the electric connection module and is used for being connected with input voltage through the electric connection module; the anode of the photodiode is connected with the inverting input end of the transimpedance amplifier so as to be connected with input voltage through the electric connection module; The cathode of