QUANTUM TUNNELING AND STOCHASTIC RESONANCE

Stochastic resonance (SR) occurs in nonlinear dynamical systems when t he response to a weak coherent input is enhanced by the presence of no ise. While classical SR presently is an intensely studied phenomenon, the role of quantum fluctuations has only started to be explored. We s tudy SR in the temperature range where quantum tunneling corrections t o the classical rate of activation are relevant. For a particle subjec t to moderate-to-large friction, we show that the semiclassical SR can be enhanced considerably by quantum fluctuations, as compared to the predictions of a classical analysis.