Nonadiabatic Quantum Brownian Rectifiers
نویسندگان
چکیده
We study both dissipative and nondissipative quantum transport in discrete Brownian rectifiers being driven by nonthermal noise that is unbiased on average. In the absence of dissipation the current is always zero and the ballistic diffusion changes into normal diffusion. The dissipative quantum dynamics exhibits current (with distinctive reversals) as a result of the cooperative interplay between dissipative forces and external fluctuations. Considering the nonlinear current response to aperiodic, noisy forces we predict aperiodic quantum stochastic resonance. The nonthermal fluctuations can considerably enhance, as well as suppress, the thermal quantum diffusion. [S0031-9007(98)06616-2]
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