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arXiv · 2009.10455

Universal Hall conductance scaling in non-Hermitian Chern insulators

Solofo Groenendijk·Thomas L. Schmidt·Tobias Meng
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Abstract

We investigate the Hall conductance of a two-dimensional Chern insulator coupled to an environment causing gain and loss. Introducing a biorthogonal linear response theory, we show that sufficiently strong gain and loss lead to a characteristic non-analytical contribution to the Hall conductance. Near its onset, this contribution exhibits a universal power-law with a power 3/2 as a function of Dirac mass, chemical potential and gain strength. Our results pave the way for the study of non-Hermitian topology in electronic transport experiments.

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Solofo Groenendijk, Thomas L. Schmidt, Tobias Meng. 2020-09-22. Universal Hall conductance scaling in non-Hermitian Chern insulators. https://doi.org/10.1103/physrevresearch.3.023001

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