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arXiv · 2112.11017

Exceptional mode topological surface laser

Kazuki Sone·Yuto Ashida·Takahiro Sagawa
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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.

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Kazuki Sone, Yuto Ashida, Takahiro Sagawa. 2021-12-21. Exceptional mode topological surface laser. https://doi.org/10.1103/physrevb.105.235426

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