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Quantum state-dependent diffusion and multiplicative noise: a microscopic approach

Debashis Barik·Deb Shankar Ray
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Abstract

The state-dependent diffusion, which concerns the Brownian motion of a particle in inhomogeneous media has been described phenomenologically in a number of ways. Based on a system-reservoir nonlinear coupling model we present a microscopic approach to quantum state-dependent diffusion and multiplicative noise in terms of a quantum Markovian Langevin description and an associated Fokker-Planck equation in position space in the overdamped limit. We examine the thermodynamic consistency and explore the possibility of observing a quantum current, a generic quantum effect, as a consequence of this state-dependent diffusion similar to one proposed by Büttiker [Z. Phys. B {\bf 68}, 161 (1987)] in a classical context several years ago.

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Debashis Barik, Deb Shankar Ray. 2005-03-28. Quantum state-dependent diffusion and multiplicative noise: a microscopic approach. https://doi.org/10.1007/s10955-005-5251-y

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