Coulomb analogy for nonhermitian degeneracies near quantum phase transitions

Cejnar, P.; Heinze, S.; Macek, M.

Coulomb analogy for nonhermitian degeneracies near quantum phase transitions

Authors

Cejnar, P.

Heinze, S.

Macek, M.

Description

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.
4 pages