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arXiv · 2311.08224

Stabilizing an ultracold Fermi gas against Fermi acceleration to superdiffusion through localization

Sian Barbosa·Maximilian Kiefer-Emmanouilidis·Felix Lang·Jennifer Koch·Artur Widera
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Abstract

Anderson localization, i.e., destructive quantum interference of multiple-scattering paths, halts transport entirely. Contrarily, time-dependent random forces expedite transport via Fermi acceleration, proposed as a mechanism for high-energy cosmic rays. Their competition creates interesting dynamics, but experimental observations are scarce. Here, we experimentally study the expansion of an ultracold Fermi gas inside time-dependent disorder and observe distinct regimes from sub- to superdiffusion. Unexpectedly, quantum interference counteracts acceleration in strong disorder. Our system enables the investigation of Fermi acceleration in the quantum-transport regime.

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Sian Barbosa, Maximilian Kiefer-Emmanouilidis, Felix Lang, Jennifer Koch, Artur Widera. 2023-11-14. Stabilizing an ultracold Fermi gas against Fermi acceleration to superdiffusion through localization. https://doi.org/10.1103/rq4w-377l

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