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CN-224216900-U - Rectangular defect cavity-based graphene ribbon metamaterial three-channel optical filter

CN224216900UCN 224216900 UCN224216900 UCN 224216900UCN-224216900-U

Abstract

The utility model relates to a graphene ribbon-shaped metamaterial three-channel optical filter based on a rectangular defect cavity, which comprises a silicon substrate, continuous graphene, a first rectangular defect cavity, a second rectangular defect cavity and a third rectangular defect cavity, wherein the continuous graphene is respectively arranged on the upper surface of the silicon substrate, and the first rectangular defect cavity, the second rectangular defect cavity and the third rectangular defect cavity are sequentially and uniformly arranged along the front-back direction of the optical filter. The utility model solves the problems of narrow bandwidth and poor filtering effect of the graphene metamaterial structure optical filter, realizes an ultra-compact structure, reduces the three-channel optical filter size of the graphene metamaterial structure, and solves the problem that the graphene metamaterial structure optical filter is not easy to integrate in an on-chip plasmon optical path.

Inventors

  • WANG BOYUN
  • YU HUAQING
  • TIAN ZHIHUI

Assignees

  • 湖北工程学院

Dates

Publication Date
20260508
Application Date
20250718

Claims (8)

  1. 1. A graphene ribbon-shaped metamaterial three-channel optical filter based on a rectangular defect cavity is characterized by comprising a silicon substrate (1), continuous graphene (2), a first rectangular defect cavity (3), a second rectangular defect cavity (4) and a third rectangular defect cavity (5), wherein: The continuous graphene (2) is arranged on the outer sides of the first rectangular defect cavity (3), the second rectangular defect cavity (4) and the third rectangular defect cavity (5) in a surrounding mode, the continuous graphene (2) is arranged continuously in the front-rear direction of the optical filter, the continuous graphene (2) is directly coupled with incident light and directly excites SPPs on the surface of the silicon substrate (1), the incident light is indirectly coupled with the first rectangular defect cavity (3), the second rectangular defect cavity (4) and the third rectangular defect cavity (5) through the continuous graphene (2), and the SPPs are indirectly excited on the surface of the first rectangular defect cavity (3), the second rectangular defect cavity (5) and the third rectangular defect cavity (4) through the continuous graphene (2).
  2. 2. The graphene ribbon-shaped metamaterial three-channel optical filter based on rectangular defect cavities according to claim 1, wherein the thickness of the silicon substrate (1) is 0.15 μm.
  3. 3. The graphene ribbon-shaped metamaterial three-channel optical filter based on rectangular defect cavities according to claim 2, wherein the length of the continuous graphene (2) is 10 μm and the width is 6 μm.
  4. 4. The graphene ribbon-shaped metamaterial three-channel optical filter based on rectangular defect cavities according to claim 3, wherein the lengths of the first rectangular defect cavity (3), the second rectangular defect cavity (4) and the third rectangular defect cavity (5) are 5.5 μm, and the widths of the first rectangular defect cavity, the second rectangular defect cavity and the third rectangular defect cavity are 1.5 μm.
  5. 5. The graphene ribbon-shaped metamaterial three-channel optical filter based on rectangular defect cavities according to claim 4, wherein a spacing between the first rectangular defect cavity (3) and the second rectangular defect cavity (4) is 0.5 μm, and a spacing between the second rectangular defect cavity (4) and the third rectangular defect cavity (5) is 0.5 μm.
  6. 6. The rectangular defect cavity-based graphene ribbon metamaterial three-channel optical filter as set forth in claim 5, wherein the thickness of the monolayer graphene adopted by the optical filter is 0.2 nm.
  7. 7. The graphene ribbon metamaterial three-channel optical filter based on rectangular defect cavities as claimed in claim 6, wherein the fermi level of the continuous graphene (2) is fixed to 1.2 eV.
  8. 8. The graphene ribbon metamaterial three-channel optical filter based on rectangular defect cavities as claimed in claim 7, wherein the optical filter is of a size on the order of microns.

Description

Rectangular defect cavity-based graphene ribbon metamaterial three-channel optical filter Technical Field The utility model relates to the technical field of optical communication, in particular to a graphene ribbon metamaterial three-channel optical filter based on a rectangular defect cavity. Background The optical filter can realize wavelength selection functions of wavelength division multiplexing, bandpass or bandstop, and is an important device in the optical communication technology. With the development of large-scale integrated all-optical devices, the small-size and dynamic tunable requirements of the multi-channel optical filter of the terahertz wave band are more and more obvious, so that the realization of the dynamic tunable multi-channel optical filter with a novel working mechanism of dynamic tunability, small size and easy integration is very important. Surface plasmons (Surface Plasmon Polaritons, SPPs for short) are a type of surface electromagnetic evanescent wave that propagates along a metal-dielectric interface and decays exponentially in the direction perpendicular to the metal surface. SPPs have the characteristics of breaking through the traditional optical diffraction limit and enhancing the strong local optical field, so that the guidance and the control of light in the sub-wavelength level can be realized. SPPs can be used as a carrier of energy and information, and have important application value in high-density integrated photon circuits. Currently, many SPPs-based photonic devices have emerged, such as bandpass filters, bandstop filters, multiplexers (demultiplexers), mach-Zehnder interferometers (MZIs), optical switches, sensors, logic gates, and the like. Because SPPs bandpass or bandstop filters have the characteristics of small loss, good out-of-band rejection and the like, and SPPs-based optical filters are important links in high-density integrated photonic circuits, a plurality of SPPs optical filters based on metamaterials and super-surface structures are presented. Thus, it is a trend in the future to realize SPPs metamaterial optical filters with compact device size, multiple channels, wide bandwidth, dynamic tunability, and ease of integration. Currently, SPPs slow light devices based on plasmon-induced transparency (Plasmon Induced Transparency, abbreviated as PIT) effect are attracting more and more attention. The generation of the PIT phenomenon is similar to the electromagnetic induction transparent (Electromagnetically Induced Transparency, EIT) effect in atomic gas, but compared with the EIT phenomenon in atomic gas, which is determined by the absorption characteristics of materials, the EIT-like phenomenon generated by the geometric structure of the resonant cavity coupled plasma waveguide system has a wider application prospect due to the characteristics of being capable of operating at room temperature, chip integration compatibility, transmission band tunability, bandwidth controllability and the like. In the metamaterial structure, PIT effect is generated by utilizing mutual coupling interference between a bright mode and a dark mode, so that the multichannel optical filter is realized. The PIT effect is suitable for application in optical filters because of the transparent peaks generated in the transmission spectrum of the PIT effect. In recent years, graphene, a two-dimensional material with a single carbon atom layer, provides a novel and low-loss way for limiting and controlling SPPs, and is widely applied to the design of SPPs devices. Considering the unique properties of graphene, graphene-based micro-nano structures can generate very strong local SPPs from the near infrared region to the terahertz band. PIT effect is generated in the graphene metamaterial structure, and the PIT effect optical filter can be dynamically tuned by changing the Fermi level of graphene. The defects of the prior art are as follows: 1. Because the traditional SPPs waveguide system generates a single PIT effect, only a single-channel optical filter can be realized, thereby causing the loss of multi-task processing capacity. 2. Because conventional SPPs optical filters are typically static and not tunable, they suffer from poor flexibility and difficulty in adapting to dynamic scenes. 3. The traditional filter based on the MZI and the fiber bragg grating has the defects of large size, adverse to large-scale integration of devices, narrow bandwidth, poor out-of-band rejection and the like, and adverse to application development of the optical filter in a broadband high-speed optical communication network. Disclosure of utility model The utility model aims to solve the problems of narrow bandwidth and poor filtering effect of a graphene strip-shaped metamaterial three-channel optical filter based on a rectangular defect cavity, realize an ultra-compact structure, reduce the size of the graphene strip-shaped metamaterial three-channel optical filter and solve the problem tha