Slow wave and truly rainbow trapping in one-way terahertz waveguide

TL;DR

This paper introduces a novel MSSM waveguide structure that achieves truly rainbow trapping of terahertz waves, enabling high-performance optical devices like buffers, switches, and filters with one-way propagation.

Contribution

The paper presents a new MSSM waveguide design that realizes truly rainbow trapping at terahertz frequencies, advancing optical device integration.

Findings

Demonstrated truly rainbow trapping in MSSM waveguides

Designed functional optical devices based on rainbow trapping

Achieved one-way wave propagation in the structure

Abstract

Slow or even stop electromagnetic (EM) waves attract researchers' attentions for its potential applications in energy storage, optical buffer and nonlinearity enhancement. However, in most cases of the EM waves trapping, the EM waves are not truly trapped due to the existence of reflection. In this paper, a novel metal-semiconductor-semiconductor-metal (MSSM) structure, and a novel truly rainbow trapping in a tapered MSSM model at terahertz frequencies are demonstrated by theoretical analysis and numerical simulations. More importantly, functional devices such as optical buffer, optical switch and optical filter are achieved in our designed MSSM structure based on truly rainbow trapping theory. Owing to the property of one-way propagation, these new types of optical devices can be high-performance and are expected to be used in integrated optical circuits.