Symmetrical terahertz polarization insensitive artificial microstructure

Abstract

The invention discloses a symmetrical terahertz polarization insensitive artificial microstructure. The microstructure is a transmission type hyperbolic surface which is provided with a centrosymmetric split ring structure, and is used for generating various resonant modes. The microstructure comprises a substrate dielectric substrate, and the substrate dielectric substrate is provided with a metal structure, wherein the metal structure is formed by periodically arranging a plurality of cross-shaped metal resonance units, each cross-shaped metal resonance unit comprises a square outer frame and a cross-shaped grating structure, and the cross-shaped grating structure is a cross-shaped grating which is arranged inside the square outer frame and the center of the cross-shaped grating structure is separated. No matter whether the vibration is LC resonance or dipole resonance, the influence of the vibration of the geometric structure on the resonance frequency and the transmission amplitude is very small. Under the excitation of TE and TM, the transmissivity results are consistent, the polarization insensitivity is realized, and the modulation depth of the unpolarized incident light high-speed modulator can be improved. Due to excitation of the high-order resonant mode, the method can be applied to various environments such as high-sensitivity biological detection and narrow-band filtering.

Description

technical field [0001] The invention relates to the technical field of terahertz modulators, in particular to a symmetrical terahertz polarization-insensitive artificial microstructure. Background technique [0002] A metasurface is a planar material consisting of a periodic array of microstructures on a dielectric substrate. It can be considered as a 2D metamaterial, a new class of materials consisting of engineered subwavelength structures for efficient performance. These artificially engineered materials are widely used due to their ability to control and manipulate electromagnetic waves from materials through structures such as modulators, detectors and generators, and optical filters. In recent decades, metasurface technology has been widely used in the terahertz frequency region. In the terahertz frequency range, it is difficult to develop electronic and optical components for the realization of terahertz technology due to the lack of suitable materials. Metasurface...

AI Technical Summary

Problems solved by technology

[0003] The technical problem to be solved by the present invention is: it is difficult for many metasurface structures to appear multiple different resonance modes at the same time. The present invention provides a symmetrical terahertz polarization-insensitive artificial microstructure that solves the above problems. The structure has multiple Two different resonant modes, under TE and TM excitation, the transmittance results are consistent, with the characteristics of polarization insensitivity, which can be used to improve the modulation depth of high-speed modulators for unpolarized incident light

Images