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arXiv · 1109.1697

A note on topological insulator phase in non-hermitian quantum systems

Pijush K. Ghosh
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Abstract

Examples of non-hermitian quantum systems admitting topological insulator phase are presented in one, two and three space dimensions. All of these non-hermitian Hamiltonians have entirely real bulk eigenvalues and unitarity is maintained with the introduction of appropriate inner-products in the corresponding Hilbert spaces. The topological invariant characterizing a particular phase is shown to be identical for a non-hermitian Hamiltonian and its hermitian counterpart, to which it is related through a non-unitary similarity transformation. A classification scheme for topological insulator phases in pseudo-hermitian quantum systems is suggested.

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Pijush K. Ghosh. 2012-02-23. A note on topological insulator phase in non-hermitian quantum systems. https://doi.org/10.1088/0953-8984%2F24%2F14%2F145302

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