Driven quantum tunneling

Feng Xu

Abstract We calculate quantum tunneling time in the double‐well system without perturbation and with symmetry‐breaking driven force using the entangled trajectory molecular dynamics method in the present article. Without perturbation, quantum tunneling time decreased with the increase of the energy, and the different contributions of the barrier traversal time and the intrinsic decay time have been shown. The tunneling time dependence on the amplitude and frequency of the symmetry‐breaking driven force are present. In the case of weak driven force, tunneling time has a minimum value in the resonant frequency. For strong driven force, chaos brings a huge change to quantum dynamics, tunneling time significantly becomes short. Finally, we directly show the enhancement of quantum tunneling process by chaotic behavior of entangled trajectories and indicate that it was caused by quantum effect.

Benjamin Bähr, Boris Lemmer, Rina Piccolo

Feng Xu

We study a wavepacket tunneling in one-dimensional periodically driven double-well system using entangled trajectory molecular dynamics method. The tunneling dynamics dependents on the amplitude and frequency of the driven force are present. Both resonant and nonresonant tunneling process are enhanced by the driven force when the system is chaotic under classical dynamics. We give entangled trajectory in phase space compared to corresponding classical trajectory with same initial state to visually show quantum tunneling process. The average values of quantum tunneling probability after long time evolution have been shown in the parameter spaces, the effect of resonance and chaos on the tunneling dynamics are present. The relation between chaos and the uncertainly product is discussed in the end. © 2016 Wiley Periodicals, Inc.

P. Kamiński, Marek Płoszajczak, Robert Arvieu

Quantum tunnelling is investigated using an exactly soluble, periodically driven Lipkin N -body model. Coherent suppression of the tunnelling is found for specific parameters of the driven force. The simple two-level model explains this behaviour qualitatively in a limited range of the driving amplitude and frequency.