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arXiv · 1709.03916

Anomalous Diffusion in a Dynamical Optical Lattice

Wei Zheng·Nigel R. Cooper
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Abstract

Motivated by experimental progress in strongly coupled atom-photon systems in optical cavities, we study theoretically the quantum dynamics of atoms coupled to a one-dimensional dynamical optical lattice. The dynamical lattice is chosen to have a period that is incommensurate with that of an underlying static lattice, leading to a dynamical version of the Aubry-Andr\'e model which can cause localization of single-particle wavefunctions. We show that atomic wavepackets in this dynamical lattice generically spread via anomalous diffusion, which can be tuned between super-diffusive and sub-diffusive regimes. This anomalous diffusion arises from an interplay between quantum localization and quantum fluctuations of the cavity field.

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Wei Zheng, Nigel R. Cooper. 2017-09-12. Anomalous Diffusion in a Dynamical Optical Lattice. https://doi.org/10.1103/physreva.97.021601

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