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arXiv · 2112.02728

Non-Hermitian total-loss high-order topological insulator based on 1D Su-Schrieffer-Heeger (SSH)

Hui-Chang Li·Jing-Wei Xu·Chen Luo·Tai-Lin Zhang·Jian-Wei Xu·Xiang Zhou·Yun Shen·Xiao-Hua Deng
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Abstract

Non-Hermiticity alters topology with the presence of non-Hermitian factors in topological systems. Most existing non-Hermitian topological systems derive their topological phases from Hermitian components, that is, the gain and loss of the system are considered simultaneously. In this work, we reveal two-dimensional non-Hermitian high-order topological insulator based on one-dimensional SSH chain, the nontrivial topology of which induced by total-loss. By introducing the loss of a specific configuration, we get a band gap with corner and edge states whose topology is characterized by the gapped wannier band. In addition, we demonstrate the existence of 'real-energy' edge states in pseudo-PT symmetric domain wall system. These results can be easily implemented in experiments, and promote the research of topological transmission of lossy systems in the real world.

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Hui-Chang Li, Jing-Wei Xu, Chen Luo, Tai-Lin Zhang, Jian-Wei Xu, Xiang Zhou, Yun Shen, Xiao-Hua Deng. 2021-12-06. Non-Hermitian total-loss high-order topological insulator based on 1D Su-Schrieffer-Heeger (SSH). https://arxiv.org/abs/2112.02728

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