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arXiv · 1708.03230

Numerical calculation of the complex berry phase in non-Hermitian systems

Marcel Wagner·Felix Dangel·Holger Cartarius·Jörg Main·Günter Wunner
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Abstract

We numerically investigate topological phases of periodic lattice systems in tight-binding description under the influence of dissipation. The effects of dissipation are effectively described by $\mathcal{PT}$-symmetric potentials. In this framework we develop a general numerical gauge smoothing procedure to calculate complex Berry phases from the biorthogonal basis of the system's non-Hermitian Hamiltonian. Further, we apply this method to a one-dimensional $\mathcal{PT}$-symmetric lattice system and verify our numerical results by an analytical calculation.

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Marcel Wagner, Felix Dangel, Holger Cartarius, Jörg Main, Günter Wunner. 2018-01-29. Numerical calculation of the complex berry phase in non-Hermitian systems. https://doi.org/10.14311/ap.2017.57.0470

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