Exceptional mode topological surface laser

TL;DR

This paper introduces a three-dimensional topological surface laser that leverages non-Hermitian topology and exceptional points to achieve robust boundary modes without the need for edge gain or symmetry protection, promising broad disorder resilience.

Contribution

It proposes a novel 3D topological laser based on non-Hermitian topology, expanding the design principles for robust topological photonic devices.

Findings

Realizes topological boundary modes without edge gain

Demonstrates robustness against disorders

Provides a feasible experimental setup

Abstract

Band topology has been studied as a design principle of realizing robust boundary modes. Here, by exploring non-Hermitian topology, we propose a three-dimensional topological laser that amplifies surface modes. The topological surface laser is protected by nontrivial topology around branchpoint singularities known as exceptional points. In contrast to two-dimensional topological lasers, the proposed three-dimensional setup can realize topological boundary modes without judicious gain at the edge or symmetry protection, which are thus robust against a broad range of disorders. We also propose a possible optical setup to experimentally realize the topological surface laser. Our results provide a general guiding principle to construct non-Hermitian topological devices in three-dimensional systems.