Exponential speedup of incoherent tunneling via dissipation
Authors: Maile D., Andergassen S., Belzig W., Rastelli G.
Autors Affiliation: Univ Konstanz, Fachbereich Phys, D-78457 Constance, Germany; Univ Tubingen, Inst Theoret Phys, Morgenstelle 14, D-72076 Tubingen, Germany; Univ Tubingen, Ctr Quantum Sci, Morgenstelle 14, D-72076 Tubingen, Germany; Univ Konstanz, Zukunftskolleg, D-78457 Constance, Germany; Univ Trento, INO CNR BEC Ctr, I-38123 Povo, Italy; Univ Trento, Dipartimento Fis, I-38123 Povo, Italy
Abstract: We study the escape rate of a particle in a metastable potential in the presence of a dissipative bath coupled to the momentum of the particle. Using the semiclassical bounce technique, we find that this rate is exponentially enhanced. In particular, the influence of momentum dissipation depends on the slope of the barrier that the particle is tunneling through. We investigate also the influence of dissipative baths coupled to the position, and to the momentum of the particle, respectively. In this case the rate exhibits a nonmonotonic behavior as a function of the dissipative coupling strengths. Remarkably, even in the presence of position dissipation, momentum dissipation can enhance exponentially the escape rate in a large range of the parameter space. The influence of the momentum dissipation is also witnessed by the substantial increase of the average energy loss during inelastic (environment-assisted) tunneling.
Journal/Review: PHYSICAL REVIEW RESEARCH
Volume: 3 (3) Pages from: 033019 to:
More Information: We acknowledge financial support from the MWK-RiSC program. This research was also partially supported by the German Excellence Initiative through the Zukunftskolleg and by the Deutsche Forschungsgemeinschaft (DFG) through the SFB 767 and Project-ID 425217212-SFB 1432. G.R. thanks P. Hauke for useful discussions and relevant comments.KeyWords: quantum dissipation, quantum brownian motion, quantum metastable stateDOI: 10.1103/PhysRevResearch.3.033019