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arXiv · 1905.07548

Topological Phase Transition Independent of System Non-Hermiticity

K. L. Zhang·H. C. Wu·L. Jin·Z. Song
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Abstract

Non-Hermiticity can vary the topology of system, induce topological phase transition, and even invalidate the conventional bulk-boundary correspondence. Here, we show the introducing of non-Hermiticity without affecting the topological properties of the original chiral symmetric Hermitian systems. Conventional bulk-boundary correspondence holds, topological phase transition and the (non)existence of edge states are unchanged even though the energy bands are inseparable due to non-Hermitian phase transition. Chern number for energy bands of the generalized non-Hermitian system in two dimension is proved to be unchanged and favorably coincides with the simulated topological charge pumping. Our findings provide insights into the interplay between non-Hermiticity and topology. Topological phase transition independent of non-Hermitian phase transition is a unique feature that beneficial for future applications of non-Hermitian topological materials.

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K. L. Zhang, H. C. Wu, L. Jin, Z. Song. 2019-07-29. Topological Phase Transition Independent of System Non-Hermiticity. https://doi.org/10.1103/physrevb.100.045141

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