Disorder-induced broadening of quantum momentum distribution

Vili Heinonen; Jani Lukkarinen

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arXiv · 2512.20170

Disorder-induced broadening of quantum momentum distribution

Vili Heinonen·Jani Lukkarinen

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Abstract

We study the long-time behavior of a non-interacting two-dimensional quantum gas in a weak random potential with long-range correlations. Any peaked initial momentum distribution will eventually become isotropic and broaden due to scattering events with the random potential. We derive an expression for the long-time average of the momentum distribution and test it against computer simulations. We also discuss momentum isotropization and spatial diffusion.

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quant-ph cond-mat.quant-gas cond-mat.stat-mech

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Vili Heinonen, Jani Lukkarinen. 2025-12-23. Disorder-induced broadening of quantum momentum distribution. https://arxiv.org/abs/2512.20170

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