Decoherence, tunneling and noise-activation in a double-potential well at high and zero temperature

摘要

We study the effects of the environment on tunneling in an open systemdescribed by a static double-well potential. We describe the evolution of aquantum state localized in one of the minima of the potential at $t=0$, both inthe limits of high and zero environment temperature. We show that the evolutionof the system can be summarized in terms of three main physical phenomena,namely decoherence, quantum tunneling and noise-induced activation, and weobtain analytical estimates for the corresponding time-scales. These analyticalpredictions are confirmed by large-scale numerical simulations, providing adetailed picture of the main stages of the evolution and of the relevantdynamical processes.