Multilayer symmetric metamaterial based on phase-change material or topological insulating material

Abstract

The invention provides a multilayer symmetric metamaterial based on a phase-change material or a topological insulating material. A resonant unit array of the multilayer symmetric metamateiral is arranged in a rectangular lattice form (namely, on the surface of the metamaterial, the horizontal cycle length Lx and the vertical cycle length Ly of a resonant unit are not equal), so that steep asymmetric Fano harmonic peaks exist in the transmission spectrum of the multilayer symmetric metamaterial; and then, the phase-change material or the topological insulating material is introduced into the multilayer symmetric metamaterial, and the Fano resonant frequency is tunable, so that the technical problem that the Fano resonant frequency cannot be changed after determination of the metamaterial structure is solved. The characteristic that the dielectric coefficient of the phase-change material or the topological insulating material changes along with the change of an extra electric field or the temperature is used in the invention, so that the tunability function of the Fano resonant frequency in the multilayer symmetric metamaterial is realized, and the maximum adjusting amplitude can be up to 40 percent.

Description

technical field [0001] The invention relates to a multi-layer symmetrical metamaterial with tunable Fano resonance phenomenon based on phase change material or topological insulating material, which can be applied to the fields of slow light, sensing, nonlinearity, optical switch and the like. Background technique [0002] In 2001, Document 1: "R.A. Shelby et al, SCIENCE, 2001(292): 77" was the first to report artificial electromagnetic metamaterials with negative refractive index in the microwave range. Since then, artificial electromagnetic metamaterials have attracted widespread attention. With the deepening of research on metamaterials, the phenomenon of Fano resonance on metamaterials has also attracted much attention. In 2007, Document 2: "V.A. Fedotove et al, PHYSICAL REVIEW LETTER, 2007(99): 147701" found Fano resonance in an asymmetric resonant ring array for the first time. However, once the structure of the metamaterial is determined, the Fano resonance character...

AI Technical Summary

Problems solved by technology

[0003] However, the above method requires a complex tuning device, which increases the complexity of the metamaterial structure design and the difficulty of the preparation process, making it difficult to apply the above tuning method to higher frequency bands such as near-infrared light bands.

Images