Stabilization of quantum metastable states by dissipation

Abstract

Normally, quantum fluctuations enhance the escape from metastable states in the presence of dissipation. Here we show that dissipation can enhance the stability of a quantum metastable system, consisting of a particle moving in a strongly asymmetric double well potential, interacting with a thermal bath. We find that the escape time from the metastable region has a nonmonotonic behavior versus the system-bath coupling and the temperature, producing a stabilizing effect

Quantum dissipative dynamics of a bistable system in the sub-Ohmic to super-Ohmic regime

“…Nevertheless it gives a good estimate for the relaxation time also in the crossover dynamical regime [46]. The master equation (17) has been used to obtain the dynamics and stationary populations in the presence of an external driving [47] and to address the problem of the escape from a quantum metastable state, starting from a nonequilibrium initial condition, with a strongly asymmetric bistable potential and Ohmic dissipation [48].…”

Nonlinear Relaxation Phenomena in Metastable Condensed Matter Systems

“…In summary, the behavior of the MFPT vs D goes with continuity from a monotonic divergent behavior to a nonmonotonic finite behavior (typical NES effect), passing through a nonmonotonic divergent behavior with a minimum and a maximum [55]. Very recently, the noise stabilizing effects were also observed in quantum systems with asymmetric bistable potentials [7].…”

“…Usually, the quantum noise and/or the dissipative environment influence in a significative way the dynamics of a quantum system characterized by a metastable state. Indeed, the decay and escape rates from a metastable state have recently received increasing interest [7,86,[164][165][166][167][168]. This problem is of general interest in many areas of physics, where the quantum systems show metastability.…”

“…takes to cross a threshold value d [7] . In the following we set the d = 0.95, meaning that we consider the particle escaped from the metastable region when the probability to detect it in the lower (right) well is equal or greater than 95%.…”

“…Specifically, metastability is a universal phenomenon in many natural systems, ranging from physics to cosmology, chemistry, biology and ecology [1][2][3][4]. Indeed, metastability is an active research field in statistical physics [5][6][7][8][9][10][11]. Understanding metastability is a fundamental issue to understand and describe the dynamical behavior of many natural systems.…”