Coulomb analogy for non-Hermitian degeneracies near quantum phase transitions.
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.
Cejnar
Pavel
P
Institute of Particle and Nuclear Physics, Faculty of Mathematics and Physics, Charles University, V Holesovickách 2, 180 00 Prague, Czech Republic.
Heinze
Stefan
S
Macek
Michal
M