Quantum system chaos in a PT-symmetry breaking potential*

We studied the dynamics of N bosons confined in a triple well potential in phase space. The system is tackled by using the truncated Wigner approximation (TWA) and exact diagonalization of Bose-Hubbard model including a perturbative PT-symmetry breaking potential. We find a region in which the symmetry breaking develops smoothly with the control parameters enabling to break many symmetries of the Hamiltonian and reduce energy degeneracies. The model shows signatures of stationarity, chaos and mixing as a consequence of the inter-particle interactions. Generation of entangled states and loss of purity is also observed and monitored by the Meyer’s measure of the impurity and the von Neumann entropy S. Finally, the system chaotic behavior is conveniently tracked within the phase space by the growth rate of the out-of-time ordered correlator.