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arXiv · 2009.03495

PT-symmetric topological near-zero interface state

Zhenjuan Liu·Kaiwen Ji·Haohao Wang·Yanan Dai·Yuanmei Gao·Yanlong Shen·Yishan Wang·Xinyuan Qi·Jintao Bai
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Abstract

Photonic systems with parity-time (PT) symmetry and topology are attracting considerable attentions. In this work, topological near-zero edge states are studied in PT-symmetric photonic lattice and the results indicate that the near-zero edge states can be broken spontaneously in spite of the unbroken PT symmetry. To achieve the stable topological near-zero mode, a binary lattice with carefully designed PT-symmetric is proposed. Further study shows such a structure supports a stable topological interface state experiences phase transition similar to the bulk states in infinite lattice and thus possess real-eigenvalues even with unbroken PT phase. Our study enriches the content of non-Hermitian topological physics and might have potential applications in the fields of topological lasing and quantum computation.

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Zhenjuan Liu, Kaiwen Ji, Haohao Wang, Yanan Dai, Yuanmei Gao, Yanlong Shen, Yishan Wang, Xinyuan Qi, Jintao Bai. 2020-10-07. PT-symmetric topological near-zero interface state. https://arxiv.org/abs/2009.03495

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