Robust Topological Terahertz Circuits using Semiconductors

TL;DR

This paper introduces semiconductor-based topological terahertz devices leveraging cyclotron resonance and magnetic fields, enabling scalable, high-functionality circuits like power splitters and circulators.

Contribution

It presents a novel approach to realize topological terahertz devices using semiconductors, overcoming optical frequency limitations of previous methods.

Findings

Proposed topological tunable power splitter

Designed topological circulator for terahertz

Demonstrated scalability and high functionality

Abstract

Topological Insulator-based devices can transport electrons/photons at the surfaces of materials without any back reflections, even in the presence of obstacles. Topological properties have recently been studied using non-reciprocal materials such as gyromagnetics or using bianisotropy. However, these effects usually saturate at optical frequencies and limit our ability to scale down devices. In order to implement topological devices that we introduce in this paper for the terahertz range, we show that semiconductors can be utilized via their cyclotron resonance in combination with small magnetic fields. We propose novel terahertz operating devices such as the topological tunable power splitter and the topological circulator. This work opens new perspectives in the design of terahertz integrated devices and circuits with high functionality.