A topological gap waveguide based on unidirectional locking of pseudo-spins

TL;DR

This paper introduces a topological gap waveguide combining topological photonic crystals and gap waveguides, achieving high transmission efficiency and robustness against defects, suitable for integrated optical communication systems.

Contribution

It presents a novel topological waveguide design that integrates topological and gap waveguide features, enhancing robustness and efficiency in photonic circuits.

Findings

High transmission efficiency demonstrated

Robustness against structural defects confirmed

Effective implementation with conventional semiconductor technology

Abstract

Photonic topological insulators (PTIs) have been widely studied due to the robustness of energy transport via supported edge modes immune to structural disorder. In this work, a topological gap waveguide is constructed by introducing line defect into a topological photonic crystal structure and combining it with a gap waveguide structure, which design therefore combines the advantages of both topological and gap waveguides. Not only does it give high transmission efficiency, but also enables high robustness for energy transmission under structural defects and sharp bends. Our proposed topological waveguide design can be implemented with conventional semiconductor technology and integrated into optical circuits for communication systems.