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arXiv · 0707.2473

Coulomb analogy for nonhermitian degeneracies near quantum phase transitions

P. Cejnar·S. Heinze·M. Macek
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Abstract

Degeneracies near the real axis in a complex-extended parameter space of a hermitian Hamiltonian are studied. We present a method to measure distributions of such degeneracies on the Riemann sheet of a selected level and apply it in classification of quantum phase transitions. The degeneracies are shown to behave similarly as complex zeros of a partition function.

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P. Cejnar, S. Heinze, M. Macek. 2007-07-17. Coulomb analogy for nonhermitian degeneracies near quantum phase transitions. https://doi.org/10.1103/physrevlett.99.100601

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