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arXiv · 1502.00443

Topological invariance and global Berry phase in non-Hermitian systems

Shi-Dong Liang·Guang-Yao Huang
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Abstract

By studying the topological invariance andBerry phase in non-Hermitian systems, we reveal the basic properties of the complex Berry phase and generalize the global Berry phases Q to identify the topological invariance for non-Hermitian systems.We find thatQcan identify topological invariance in two kinds of non-Hermitian model, the two-level non-Hermitian Hamiltonian and the bipartite dissipative model. For the bipartite dissipative model, an abrupt change of the Berry phase in the parameter space reveals a quantum phase transition and is related to the exceptional points. These results give the basic relationships between the Berry phase and the quantum and topological phase transitions of non-Hermitian systems.

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Shi-Dong Liang, Guang-Yao Huang. 2015-02-02. Topological invariance and global Berry phase in non-Hermitian systems. https://doi.org/10.1103/physreva.87.012118

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