arXiv:1812.04166 · Physical review. B./Physical review. B

Quantum diffusion in the strong tunneling regime

Nisarga Paul, Ariel Amir

Published Jul 26, 2019• 3 citations

Abstract

We study the spread of a quantum-mechanical wave packet in a noisy environment, modeled using a tight-binding Hamiltonian. Despite the coherent dynamics, the fluctuating environment may give rise to diffusive behavior. When correlations between different level-crossing events can be neglected, we use the solution of the Landau-Zener problem to find how the diffusion constant depends on the noise. We also show that when an electric field or external disordered potential is applied to the system, the diffusion constant is suppressed with no drift term arising. The results are relevant to various quantum systems, including exciton diffusion in photosynthesis and electronic transport in solid-state physics.

DOI: 10.1103/physrevb.100.024110

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