CN-121978832-A - Vertical grating coupler design method, device, equipment and readable storage medium

CN121978832ACN 121978832 ACN121978832 ACN 121978832ACN-121978832-A

Abstract

The method, the device, the equipment and the readable storage medium for designing the vertical grating coupler are characterized in that a design area and configuration of each layer structure are determined by depending on a standard composite substrate platform, a design platform comprising an input-output light field mode is established in an electromagnetic field simulation environment, an optimization target with coupling efficiency as a core is definitely established, light field mode characteristics of an anti-resonance hollow fiber are anchored from a design source, an optimization direction is directly aligned with actual distribution requirements, a foundation is laid for accurate adaptation, medium distribution of the design area is described by a normalization variable, iteration optimization is realized by combining process constraint through forward simulation, sensitivity solving and variable updating, wide spectrum transmission requirements are synchronously adapted, the medium distribution form can be automatically optimized according to field distribution characteristics of the anti-resonance hollow fiber by the algorithm, efficient adaptation of a light field can be realized without additional transition structures, and field distribution deviation caused by single wavelength adaptation is avoided.

Inventors

LI JIAHAO
QIU YING
LUO MING
ZHANG XU

Assignees

武汉邮电科学研究院有限公司
鹏城实验室

Dates

Publication Date: 20260505
Application Date: 20260113

Claims (10)

1. The design method of the anti-resonance hollow fiber vertical grating coupler is characterized by comprising the following steps of: determining a design area and configuration of each layer structure based on a standard composite substrate platform, establishing a design platform comprising an input/output light field mode in an electromagnetic field simulation environment, and definitely taking coupling efficiency as a core optimization target; Adopting a topology optimization algorithm, describing the medium distribution of a design area by using normalized variables, realizing iterative optimization by combining process constraint through forward simulation, sensitivity solving and variable updating, and synchronously adapting to the wide spectrum transmission requirement; And outputting a grating structure design file of the adaptation standard manufacturing process after the optimization target meets the convergence condition.
2. The method for designing an antiresonant hollow fiber vertical grating coupler according to claim 1, The method adopts a topology optimization algorithm to describe the medium distribution of a design area by a normalized variable, combines process constraint to realize iterative optimization through forward simulation, sensitivity solving and variable updating, and synchronously adapts to wide spectrum transmission requirements, and comprises the following steps: Constructing a core algorithm framework of iterative optimization by adopting a topology optimization algorithm based on an accompanying field based on a characterization result of medium distribution of a design area by using a normalization variable; inputting medium distribution data represented by normalized variables by means of a constructed electromagnetic field simulation environment, and obtaining light field distribution in a design area by solving an electromagnetic field basic equation set; Based on the light field distribution obtained by forward simulation, solving an electromagnetic field equation set in a conjugate form to obtain accompanying field distribution, and deducing the sensitivity distribution of an optimization target to a normalized variable through the interaction relation between the light field and the accompanying field; And updating the normalized variable by using a gradient optimization strategy with sensitivity distribution as a guide, and correcting through spatial filtering and projection processing to ensure that the normalized variable meets process constraint and form an effective variable which can be used for the next iteration.
3. The method of designing an antiresonant hollow fiber vertical grating coupler according to claim 2, further comprising the steps of: In a single iteration process of forward simulation, sensitivity solving and variable updating, a plurality of wavelength points are synchronously selected in a common wave band of optical communication, light field distribution and sensitivity distribution of each wavelength point are respectively obtained, and a variable updating strategy is adjusted by combining optimization target requirements under multiple wavelengths, so that an iteration optimization result can adapt to wide spectrum transmission requirements.
4. The method for designing an antiresonant hollow fiber vertical grating coupler according to claim 2, The characterization result of the medium distribution in the design area based on the normalized variable comprises the following steps: the dielectric distribution of the design area is represented by adopting a normalized variable with a value range being a normalized interval, and the corresponding relation between the normalized variable and the actual dielectric constant of the design area is established through a dielectric constant linear interpolation formula, wherein the dielectric constant linear interpolation formula takes dielectric constants of silicon and silicon dioxide as basic parameters; the correction is carried out through space filtering and projection processing, so that normalized variables meet process constraints, and the correction comprises the following steps: performing process adaptation on the normalized variable through spatial filtering and projection processing, wherein the spatial filtering adopts weighted average check to smooth the normalized variable so as to eliminate structural features smaller than a process permission threshold; The projection processing adopts a step-type projection function to lead the normalized variable to trend towards discrete values corresponding to two media, so as to ensure that the two media of silicon and silicon dioxide form a clear boundary.
5. The method for designing an antiresonant hollow fiber vertical grating coupler according to claim 1, The method for determining the design area and the configuration of each layer structure based on the standard composite substrate platform, establishing a design platform comprising an input/output light field mode in an electromagnetic field simulation environment, and definitely taking coupling efficiency as a core optimization target comprises the following steps: Selecting a silicon-silicon dioxide-silicon composite substrate platform as a standard composite substrate platform, defining a design area on the platform and determining each layer of structural configuration, wherein each layer of structural configuration comprises a core functional layer, an optical isolation layer and an optional top protection layer; constructing an electromagnetic field simulation environment through a photon simulation tool, loading an anti-resonance hollow fiber main mode in the electromagnetic field simulation environment as an input optical field mode, and loading a silicon-based waveguide fundamental mode as an output optical field mode to form a design platform comprising the input optical field mode and the output optical field mode; the power overlap integration maximization of the input light field mode and the output light field mode serves as an optimization target with the coupling efficiency as a core.
6. The method for designing an antiresonant hollow fiber vertical grating coupler according to claim 5, further comprising the steps of: When the structural configuration of each layer is determined, the bottom metal anti-reflection layer is not arranged in the design area, the optical isolation layer is adopted to replace the traditional metal reflection layer, and the light field guiding and substrate leakage inhibiting functions are realized through the structural parameter design of the optical isolation layer.
7. The method for designing an antiresonant hollow fiber vertical grating coupler according to claim 1, Outputting a grating structure design file of an adaptation standard manufacturing process after the target to be optimized meets the convergence condition, wherein the grating structure design file comprises the following components: Setting that in a plurality of rounds of continuous iteration, the comprehensive optimization objective function variable quantity corresponding to the coupling efficiency, the working bandwidth and the minimum feature size is smaller than a preset threshold value, wherein the coupling efficiency reaches a preset optimal level, the working bandwidth meets a preset range requirement, and the minimum feature size meets a process permission standard as a convergence condition; and outputting the grating structure design file when the optimization target meets the convergence condition.
8. An anti-resonance hollow fiber vertical grating coupler design device, characterized in that the anti-resonance hollow fiber vertical grating coupler design device comprises: The basic construction module is used for determining a design area and configuration of each layer of structure based on a standard composite substrate platform, establishing a design platform comprising an input and output light field mode in an electromagnetic field simulation environment, and definitely taking coupling efficiency as a core optimization target; the iterative optimization module is used for adopting a topology optimization algorithm to describe the medium distribution of the design area by using normalized variables, realizing iterative optimization by combining process constraint through forward simulation, sensitivity solving and variable updating, and synchronously adapting to the wide spectrum transmission requirement And the result output module is used for outputting a grating structure design file of the adaptation standard manufacturing process after the optimization target meets the convergence condition.
9. An antiresonant hollow fiber optic vertical grating coupler design device comprising a processor, a memory, and an antiresonant hollow fiber optic vertical grating coupler design program stored on the memory and executable by the processor, wherein the antiresonant hollow fiber optic vertical grating coupler design program, when executed by the processor, implements the steps of the antiresonant hollow fiber optic vertical grating coupler design method of any of claims 1-7.
10. A computer readable storage medium, wherein an anti-resonant hollow fiber vertical grating coupler design program is stored on the computer readable storage medium, wherein the anti-resonant hollow fiber vertical grating coupler design program, when executed by a processor, implements the steps of the anti-resonant hollow fiber vertical grating coupler design method of any one of claims 1 to 7.

Description

Vertical grating coupler design method, device, equipment and readable storage medium Technical Field The application relates to the field of optical fiber communication and integrated photonics intersection, in particular to a method, a device, equipment and a readable storage medium for designing a vertical grating coupler. Background At present, the cross field of optical fiber communication and integrated photonics develops rapidly, the anti-resonance hollow optical fiber is increasingly urgent in the front scenes such as quantum communication systems, data center optical interconnection, high-density photonic integrated circuits, high-power laser transmission and the like by virtue of the outstanding advantages such as ultra-low transmission loss, wide spectrum transmission, low-beam speed transmission, nonlinear effect resistance, excellent environmental robustness and the like, particularly in the application scenes with strict requirements on single photon transmission efficiency, and a high-efficiency coupling device is needed to realize low-loss connection of the coupling device and a silicon-based photonic chip. In the related art, the coupling of the conventional optical fiber and the silicon-based chip mostly adopts an edge coupling or inclined grating structure, and the conventional grating coupler is designed for a common single-mode optical fiber, and the coupling is usually realized by compensating loss through a long tapered waveguide or a multilayer reflection structure. However, the conventional grating coupler is usually designed for a common single-mode fiber, the periodic structure of the conventional grating coupler is difficult to adapt to the wide mode field distribution of the anti-resonance hollow fiber, and the loss is compensated by relying on a long tapered waveguide or a metal reflecting layer, so that the size of the device is oversized and the complexity of the process is high. Disclosure of Invention The application provides a method, a device, equipment and a readable storage medium for designing a vertical grating coupler, which can solve the technical problems that the traditional coupling scheme cannot adapt to the wide mode field distribution of an anti-resonance hollow fiber, the coupling efficiency is low due to mode mismatch, the size of a device is overlarge, and the process complexity is high in the related art. In a first aspect, an embodiment of the present application provides a method for designing an anti-resonant hollow fiber bragg grating vertical grating coupler, where the method for designing an anti-resonant hollow fiber bragg grating vertical grating coupler includes: determining a design area and configuration of each layer structure based on a standard composite substrate platform, establishing a design platform comprising an input/output light field mode in an electromagnetic field simulation environment, and definitely taking coupling efficiency as a core optimization target; Adopting a topology optimization algorithm, describing the medium distribution of a design area by using normalized variables, realizing iterative optimization by combining process constraint through forward simulation, sensitivity solving and variable updating, and synchronously adapting to the wide spectrum transmission requirement; And outputting a grating structure design file of the adaptation standard manufacturing process after the optimization target meets the convergence condition. With reference to the first aspect, in an implementation manner, the adopting a topology optimization algorithm to describe the medium distribution of the design area by using normalized variables, and implementing iterative optimization by combining process constraints through forward simulation, sensitivity solving and variable updating, and synchronously adapting to the wide spectrum transmission requirement includes: Constructing a core algorithm framework of iterative optimization by adopting a topology optimization algorithm based on an accompanying field based on a characterization result of medium distribution of a design area by using a normalization variable; inputting medium distribution data represented by normalized variables by means of a constructed electromagnetic field simulation environment, and obtaining light field distribution in a design area by solving an electromagnetic field basic equation set; Based on the light field distribution obtained by forward simulation, solving an electromagnetic field equation set in a conjugate form to obtain accompanying field distribution, and deducing the sensitivity distribution of an optimization target to a normalized variable through the interaction relation between the light field and the accompanying field; And updating the normalized variable by using a gradient optimization strategy with sensitivity distribution as a guide, and correcting through spatial filtering and projection processing to ensure that the normalized variabl