A dynamical signature of quantum chaos in hydrogen atom under strong, oscillating magnetic fields

Abstract

A dynamical signature of quantum chaos is proposed in terms of the nonlinear growth of time-dependent (TD) distance function between two trajectories, corresponding to two slightly different Hamiltonians, in what is defined as Ehrenfest phase space. Through comparisons of this signature with the TD correlation function and the Loschmidt echo in case of the hydrogen atom in strong, oscillating magnetic fields, the effectiveness of the proposed signature is demonstrated.