Quantum Diffusion in the Strong Tunneling Regime

Abstract

We study the spread of a quantum-mechanical wavepacket 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.

arXiv comment7 pages, 4 figures

References in corpus (8)

• Environment-Assisted Quantum Walks in Photosynthetic Energy Transfer
• Dephasing assisted transport: Quantum networks and biomolecules
• Quantum transport simulations in a programmable nanophotonic processor
• Transition times in the Landau-Zener model
• Classical Diffusion of a quantum particle in a noisy environment
• Quantum Diffusion on Molecular Tubes: Universal Scaling of the 1D to 2D Transition
• Super-diffusion in optical realizations of Anderson localization
• Enhanced transport when Anderson localization is destroyed