Francisco Pérez-Bernal

Degeneracy beyond the parity-symmetry protection in the Lipkin-Meshkov-Glick model

Degeneracy patterns in quantum mechanics stem from the system symmetries. In particular, the broken-symmetry phase in the well-known Lipkin-Meshkov-Glick (LMG) model is composed of doubly-degenerate states of different parity. In this work, we show that such doublets can exist even if parity is not conserved. For this...