Anisotropy-driven transition from collisionless to collisional regime in the dipolar modes of a trapped gaseous mixture

P. Capuzzi; P. Vignolo; M. P. Tosi

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Anisotropy-driven transition from collisionless to collisional regime in the dipolar modes of a trapped gaseous mixture

P. Capuzzi·P. Vignolo·M. P. Tosi

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Abstract

We evaluate the dipolar oscillations of a harmonically trapped fermion gas containing thermal bosonic impurities as a function of the anisotropy of the trap, from the numerical solution of the Vlasov-Landau equations for the one-body phase-space distribution functions. Starting from a situation in which the two components of the gaseous mixture perform almost independent oscillations inside a spherical trap, we demonstrate that different collision behaviors arise for oscillations in different directions as the trap is deformed into an elongated cigar-like shape. An increase in the anisotropy of the confinement thus suffices to drive a transition of dipolar modes from a collisionless to a collisional regime.

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P. Capuzzi, P. Vignolo, M. P. Tosi. 2005-01-27. Anisotropy-driven transition from collisionless to collisional regime in the dipolar modes of a trapped gaseous mixture. https://arxiv.org/abs/cond-mat/0408654

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