CN-121596460-B - Tunable topology Gu Tapu photonic crystal filter with multi-wavelength notch

CN121596460BCN 121596460 BCN121596460 BCN 121596460BCN-121596460-B

Abstract

The invention discloses a multi-wavelength notch adjustable topology Gu Tapu photonic crystal filter which comprises a waveguide interface, a first valley topology photonic crystal and a second valley topology photonic crystal, wherein the first valley topology photonic crystal comprises a plurality of first regular hexagonal cells, sector-shaped medium columns are arranged at three alternate vertexes of a single first regular hexagonal cell, each first regular hexagonal cell is arranged in a honeycomb array to obtain N circular medium columns with the radius of R, the second valley topology photonic crystal comprises a plurality of second regular hexagonal cells, sector-shaped medium columns are arranged at three alternate vertexes of the single second regular hexagonal cell, the sign of the valley Chen Shu of each second regular hexagonal cell is opposite to that of the valley Chen Shu of the first regular hexagonal cell, each second regular hexagonal cell is arranged in a honeycomb array to obtain M circular medium columns, the radius of the M1 circular medium columns is R, the radius of the M2 circular medium columns is larger than R, and M1+M2=M. The invention can realize the multi-wavelength interval notch function.

Inventors

XU XIAOFANG
LI JIN
RAO ZHONGTIAN
Han Zongyue
WU JUN
DI JIANKE
ZHOU XIAOXI

Assignees

苏州城市学院

Dates

Publication Date: 20260512
Application Date: 20260130

Claims (7)

1. The tunable topology Gu Tapu photonic crystal filter with the multi-wavelength notch is characterized by comprising a waveguide interface, and a first valley topology photonic crystal and a second valley topology photonic crystal which are distributed on two sides of the waveguide interface; the first valley topology photonic crystal comprises a plurality of first regular hexagon unit cells, wherein fan-shaped medium columns are respectively arranged at three alternate vertexes of a single first regular hexagon unit cell, each first regular hexagon unit cell is arranged in a honeycomb array with a lattice constant a as a period length to obtain N circular medium columns, and the radiuses of the N circular medium columns are all R; The second valley topology photonic crystal comprises a plurality of second regular hexagonal unit cells, wherein sector dielectric columns are respectively arranged at three alternate vertexes of each second regular hexagonal unit cell, the sign of the valley Chen Shu is opposite to that of the valley Chen Shu of each first regular hexagonal unit cell, each second regular hexagonal unit cell is arranged in a honeycomb array with the lattice constant a as the period length to obtain M circular dielectric columns, the radius of each M1 circular dielectric column is R, the radius of each M2 circular dielectric columns is larger than R, the circular dielectric columns with the radius larger than R are defined as defect columns, M1+M2=M and M1 is larger than M2; the radius of the defect column is in the range of 0.480a-0.485a; When the number of the defect columns is greater than 1, the radii of the defect columns are different, and the intervals between the resonance wavelengths corresponding to the defect columns are different and can be independently set.
2. The tunable topology Gu Tapu photonic crystal filter of multi-wavelength notch of claim 1, wherein each of the defect columns is independent of each other and is sequentially disposed along an extension direction of the waveguide interface when the number of defect columns is greater than 1.
3. The tunable topology Gu Tapu photonic crystal filter of multi-wavelength notch of claim 1, wherein when the number of defective columns is greater than 1, each defective column is located in the same row or in a different row and is sequentially arranged along the extension direction of the waveguide interface.
4. The tunable topology Gu Tapu photonic crystal filter with multi-wavelength notch, as set forth in claim 1, wherein the waveguide interface is saw-tooth shaped, and the saw-tooth waveguide interface is formed by fan-shaped dielectric columns at the upper left and upper right vertices of the first regular hexagonal unit cells distributed on one side of the waveguide interface and fan-shaped dielectric columns at the lower left and lower right vertices of the second regular hexagonal unit cells distributed on the other side of the waveguide interface in a staggered and meshed arrangement along the extending direction of the waveguide.
5. The tunable topology Gu Tapu photonic crystal filter with multi-wavelength notch as recited in claim 4, wherein the operating band of the topological boundary state supported by the saw-tooth waveguide interface is 172.588 THz to 199.417 THz when the lattice constant a is 560 nm and R is 0.3 a.
6. The multi-wavelength notch tunable topology Gu Tapu photonic crystal filter of claim 1, wherein the sector dielectric pillars are made of electro-optically tunable material.
7. The tunable topology Gu Tapu photonic crystal filter with multi-wavelength notch as recited in claim 6, wherein the sector dielectric posts are made of barium titanate material.

Description

Tunable topology Gu Tapu photonic crystal filter with multi-wavelength notch Technical Field The invention belongs to the technical field of photonic crystals, and particularly relates to a multi-wavelength notch tunable topology Gu Tapu photonic crystal filter. Background Topology photonics realizes the steady regulation and control of electromagnetic waves by introducing topology physical states, and particularly valley photonic crystals are paid attention to because no external magnetic field is needed, all-medium realization is realized and the technology is compatible with CMOS technology. Devices based on valley topology boundary states have been used in waveguide, coupler, etc. scenarios. However, the related art has the following major drawbacks: 1. error sensitivity the traditional waveguide structure is very sensitive to manufacturing error, and tiny process flaws may lead to rapid degradation of device performance and low yield 2. The operating frequency is difficult to adjust, and the operating frequency of most topological photonic devices (such as topological waveguides) is determined by geometric parameters, and once the preparation is completed, the frequency is fixed, so that the application of the topological photonic devices in controllable spectrum modulation is limited. 3. The existing tunable filter usually depends on thermal tuning, mechanical tuning or complex multi-cavity coupling structure, and has the problems of low tuning efficiency, high power consumption or insufficient device integration level. 4. There is a free spectral range limitation in that when multiple wavelengths are filtered, the wave response exhibits strict periodicity, and it is difficult to meet the requirements of the next generation optical network for non-uniform, arbitrary wavelength interval channel allocation. Disclosure of Invention Aiming at the problems, the invention provides a tunable topology Gu Tapu photonic crystal filter with multi-wavelength notch, which can realize the function of multi-wavelength interval notch. In order to achieve the technical purpose and achieve the technical effect, the invention is realized by the following technical scheme: a tunable topology Gu Tapu photonic crystal filter with multi-wavelength notch comprises a waveguide interface, and a first valley topology photonic crystal and a second valley topology photonic crystal distributed on two sides of the waveguide interface; the first valley topology photonic crystal comprises a plurality of first regular hexagon unit cells, wherein fan-shaped medium columns are respectively arranged at three alternate vertexes of a single first regular hexagon unit cell, each first regular hexagon unit cell is arranged in a honeycomb array with a lattice constant a as a period length to obtain N circular medium columns, and the radiuses of the N circular medium columns are all R; The second valley topology photonic crystal comprises a plurality of second regular hexagonal unit cells, wherein sector dielectric columns are respectively arranged at three alternate vertexes of each second regular hexagonal unit cell, the sign of each valley Chen Shu is opposite to that of each valley Chen Shu of each first regular hexagonal unit cell, each second regular hexagonal unit cell is arranged in a honeycomb array with a lattice constant a as the period length, M circular dielectric columns are obtained, the radius of each M1 circular dielectric column is R, the radius of each M2 circular dielectric columns is larger than R, circular dielectric columns with the radius larger than R are defined as defect columns, M1+M2=M, and M1 is larger than M2. Optionally, the radius of the defect column ranges from 0.480a to 0.485a. Alternatively, when the number of the defective columns is greater than 1, the defective columns are independent of each other and are sequentially arranged along the extending direction of the waveguide interface. Alternatively, when the number of defective columns is greater than 1, the defective columns are located in the same row or different rows, and are sequentially arranged along the extending direction of the waveguide interface. Optionally, when the number of the defective columns is greater than 1, the radii of the defective columns are different, and the intervals between the resonance wavelengths corresponding to the defective columns are different. Optionally, the waveguide interface is zigzag, and the zigzag waveguide interface is formed by fan-shaped dielectric columns at the upper left vertex and the upper right vertex of the first regular hexagonal unit cells distributed at one side of the waveguide interface and fan-shaped dielectric columns at the lower left vertex and the lower right vertex of the second regular hexagonal unit cells distributed at the other side of the waveguide interface in a staggered and meshed arrangement along the extending direction of the waveguide. Optionally, when the lattice constant a i