Driving and dissipation stabilizing quantum metastable states

Usually, quantum fluctuations enhance the escape from a quantum dissipative metastable state. A critical issue is whether the dissipation and/or an external driving force can enhance the stability of quantum metastable states. Here, we show that dissipation and driving can enhance the stability of a quantum metastable system strongly interacting with a thermal bath. We find that the escape time from the metastable region, with unstable initial condition, has a nonmonotonic behavior versus the system-bath coupling and the temperature, producing a stabilizing effect. Moreover, the combined effects of strong Ohmic dissipation and monochromatic driving give rise to an additional nonmonotonic behavior as a function of the driving frequency. The quantum noise enhanced stability phenomenon is observed in the system investigated. Moreover, by investigating the resonantly activated escape from a quantum metastable state with strong Ohmic dissipation in the presence of a fluctuating driving field, the quantum stochastic resonant activation phenomenon is observed. These results shed new light on the role of the environmental fluctuations in stabilizing quantum metastable systems, to control the escape dynamics, and exploit dissipation induced steady states for quantum computation.