Topological membrane devices for terahertz on-chip photonics

TL;DR

This paper presents the design and experimental validation of topological membrane devices for terahertz on-chip photonics, offering miniaturization, robustness, and new functionalities for terahertz systems.

Contribution

It introduces topological membrane metasurfaces for terahertz on-chip photonics, enabling integrated, miniaturized, and robust devices with novel topological features.

Findings

Demonstrated valley-locked asymmetric energy flow

Realized mode conversion with topological waveguides

Implemented multi-port couplers and whispering gallery resonators

Abstract

Terahertz waves offer a profound platform for next-generation sensing, imaging, and information communications. However, all conventional terahertz components and systems suffer from a bulky design, sensitivity to imperfections, and transmission losses. Here, we propose and experimentally demonstrate on-chip integration and miniaturization of topological devices which may address many existing drawbacks of the terahertz technology. We design and fabricate topological devices based on valley-Hall photonic structures that can be employed for various integrated components of on-chip terahertz systems. More specifically, we demonstrate the valley-locked asymmetric energy flow and mode conversion with topological straight waveguide, multi-port couplers, wave division, and whispering gallery mode resonators. Our devices are based on topological membrane metasurfaces which are of great importance for developing on-chip photonics and bringing many novel features into terahertz devices.