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Interatomic collisions in a tightly confined Bose gas

D. S. Petrov·G. V. Shlyapnikov
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Abstract

We discuss pair interatomic collisions in a Bose gas tightly confined in one (axial) direction and identify two regimes of scattering. In the quasi2D regime, where the confinement frequency $ω_0$ greatly exceeds the gas temperature $T$, the scattering rates exhibit 2D features of the particle motion. At temperatures $T\sim\hbarω_0$ one has a confinement-dominated 3D regime, where the confinement can change the momentum dependence of the scattering amplitudes. We describe the collision-induced energy exchange between the axial and radial degrees of freedom and analyze recent experiments on thermalization and spin relaxation rates in a tightly (axially) confined gas of Cs atoms.

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D. S. Petrov, G. V. Shlyapnikov. 2000-12-06. Interatomic collisions in a tightly confined Bose gas. https://doi.org/10.1103/physreva.64.012706

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