Terahertz detector

Abstract

The invention provides a terahertz detector. The terahertz detector comprises a substrate layer; a metal reflecting layer which is arranged on the substrate layer; a dielectric spacer layer which is arranged on the metal reflecting layer; a first Dirac semimetal layer and a second Dirac semimetal layer which are symmetrically arranged on the dielectric spacer layer; and a metal grating layer which is arranged on the dielectric spacer layer and is positioned between the first Dirac semimetal layer and the second Dirac semimetal layer. According to the terahertz detector, a composite structure of the anisotropic optical antenna and the Dirac semimetal layer is designed, and high polarization discrimination excitation and impedance matching coupling are based on the plasmon resonant cavity; incident light with the polarization direction perpendicular to the metal grating is efficiently converted into a sub-wavelength strong light field fully overlapped with the Dirac semimetal layer. According to the device, the light absorption and the light response of the Dirac semimetal layer are greatly improved, and the device has a higher polarization extinction ratio, a higher integration level, a higher response rate and lower power consumption.

Description

technical field [0001] The invention relates to the technical field of photodetectors, in particular to a terahertz detector. Background technique [0002] The emergence of topological Dirac semimetals provides an ideal experimental regime for the discovery of new quasiparticles that are often elusive in high-energy physics, such as Dirac fermions, Weyl fermions, and other exotic new quantum state. The discovery of topological insulators and topological semimetals has drawn attention to fundamental excitations and nontrivial topological features in solid-state crystals, especially Weyl semimetals and Dirac semimetals, which can have Wide range of applications. [0003] Studies have shown that materials belonging to the second class of topological Dirac semimetals will lead to some new quantum phenomena, such as field selectivity anomalies and chiral mode inversion and new mechanisms for entropy transport. A single Weyl point in a material has well-defined chirality, and i...

AI Technical Summary

Problems solved by technology

[0007] The invention provides a terahertz detector, which aims to solve the technical problems of low integration, low response rate, high power consumption and insufficient detection sensitivity of the prior art photodetector

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