Terahertz metamaterials with modulators and slow-light capabilities

Abstract

The invention provides a terahertz metamaterial with a modulator and a slow light function. The terahertz metamaterial comprises a metal electrode and a metamaterial body, wherein the metamaterial body consists of a substrate, a metal resonance unit and a graphene strip; the substrate is provided with an insulation layer; the metal resonance unit and the graphene strip are arranged on the insulation layer of the substrate; the bias voltage is externally applied to the metamaterial body by the metal electrode, and the Fermi energy level of the graphene is adjusted, so as to regulate and controlthe transmittance of terahertz electromagnetic waves and the slow light effect. The terahertz metamaterial has the advantages that the problem of regulating and controlling on the mutual-coupling strength of open and dark-mode resonance structures in the metamaterial is solved, so as to realize the space modulation of the terahertz waves; the strong dispersion characteristic is produced by electromagnetically induced transparency, the delay of the electromagnetic wave group is produced, the slow light function is realized, and the slow light effect can be regulated and controlled by externally applying offset bias to change the Fermi energy level of the graphene; in the modulation process, the wave transmittance condition at the transparent peak frequency point is changed, the other frequency points are not affected, and the possible modulation noise can be effectively avoided.

Description

technical field [0001] The invention relates to the technical field of metamaterials, in particular to a terahertz metamaterial with modulator and slow light functions. Background technique [0002] The first discovery of electromagnetically induced transparency was in tertiary atomic systems. Electromagnetically induced transparency refers to the emergence of a narrow-band transparent frequency window in an opaque medium. This phenomenon is accompanied by strong dispersion and light-particle interaction, so it can be used in various fields such as slow light effects and detectors. [0003] Metamaterials can produce physical phenomena similar to electromagnetically induced transparency, which overcomes various constraints such as low-temperature optical pumping of atomic systems. There are two main mechanisms for metamaterials to produce electromagnetically induced transparency: one is the coupling of bright and dark modes, and the other is the coupling of bright and brigh...

AI Technical Summary

Problems solved by technology

The existing research is to directly change the resonant structure of the metamaterial by directly adjusting the Fermi level of the graphene through the simple combination of graphene and metamaterials to achieve the purpose of regulating the THz transmission curve, thereby realizing the THz modulator However, the modulation depth of this method is limited and needs to be further improved

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