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arXiv · 0806.3529

Geometric phases and quantum phase transitions in open systems

Alexander I. Nesterov·S. G. Ovchinnikov
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Abstract

The relationship between quantum phase transition and complex geometric phase for open quantum system governed by the non-Hermitian effective Hamiltonian with the accidental crossing of the eigenvalues is established. In particular, the geometric phase associated with the ground state of the one-dimensional dissipative Ising model in a transverse magnetic field is evaluated, and it is demonstrated that related quantum phase transition is of the first order.

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Alexander I. Nesterov, S. G. Ovchinnikov. 2008-06-22. Geometric phases and quantum phase transitions in open systems. https://doi.org/10.1103/physreve.78.015202

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