Optical waveguide structure capable of regulating and controlling boundary state of topological photonic crystal

Abstract

The invention provides an optical waveguide structure capable of regulating and controlling the boundary state of a topological photonic crystal. The optical waveguide structure comprises an upper metal plate, a lower metal plate, a waveguide, a background material and a shell, wherein the upper metal plate and the lower metal plate are arranged in the shell, the waveguide is arranged between theupper metal plate and the lower metal plate, the waveguide is composed of a part A and a part B, the part A is formed by arranging unit cells with moderate topological properties, the part B is formedby arranging unit cells with non-moderate topological properties, each unit cell is formed by arranging six cylindrical dielectric cylinders with the radius of 0.12a, the cross section of each unit cell is in a regular hexagon shape, the distance radius from the center of each unit cell to the corresponding cylindrical dielectric cylinder in the unit cell is R, the distance between the centers ofevery two adjacent unit cells is a lattice constant a, the unit cells with the moderate topological property meet a / R=3.36, and the unit cells with the non-moderate topological property meet a / R=2.8.The problems that a traditional waveguide photon is weak in locality and low in transmission efficiency, and the frequency cannot be regulated and controlled are solved.

Description

Technical field

[0001] The invention relates to a photonic crystal optical waveguide structure, in particular to an optical waveguide structure capable of regulating the boundary state of a topological photonic crystal.Background technique

[0002] Realizing the quantum spin Hall effect, obtaining stable boundary modes and photonic pseudo-spin mechanism, topological photonic crystals have become a hot research topic. Based on C6The symmetrical honeycomb photonic crystal structure can realize the energy band reversal of the photonic band gap from closed to open without external magnetic field or low temperature, and the edge state protected by the topology appears. The interaction between light and matter in the photonic crystal structure is used to design optical waveguide devices with superior performance, which provides a new direction for applications such as non-reciprocal filters and tunable spin switches.

[0003] At present, the topological boundary state of unidirectional transmission...

Images