Strong-damping limit of quantum Brownian motion in a disordered environment

Arthur M. Faria; Marcus V. S. Bonanca; Eric Lutz

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arXiv · 2502.20174

Strong-damping limit of quantum Brownian motion in a disordered environment

Arthur M. Faria·Marcus V. S. Bonanca·Eric Lutz

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Abstract

We consider a microscopic model of an inhomogeneous environment where an arbitrary quantum system is locally coupled to a harmonic bath via a finite-range interaction. We show that in the overdamped regime the position distribution obeys a classical Kramers-Moyal equation that involves an infinite number of higher derivatives, implying that the finite bath correlation length leads to non-Gaussian Markovian noise. We analytically solve the equation for a harmonically bound particle and analyze its non-Gaussian diffusion as well as its steady-state properties.

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Arthur M. Faria, Marcus V. S. Bonanca, Eric Lutz. 2025-02-27. Strong-damping limit of quantum Brownian motion in a disordered environment. https://arxiv.org/abs/2502.20174

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