Loschmidt echo for the many-electron dynamics in nonparabolic quantum wells

The Loschmidt echo (or quantum fidelity) is investigated in the context of the many-body electron dynamics in a nonparabolic quantum well, modeled by the self-consistent Wigner-Poisson system. The quantum fidelity drops abruptly after a quiescent period, as was observed for other self-interacting systems. A unifying interpretation of this phenomenon is given in terms of trajectory separation and the Ehrenfest time. The effects of Planck's constant and environment-induced decoherence are also studied.