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arXiv · 1310.6386

Landau damping in a collisionless dipolar Bose gas

Stefan S. Natu·Ryan M. Wilson
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Abstract

We present a theory for the Landau damping of low energy quasi-particles in a collisionless, quasi-2D dipolar Bose gas and produce expressions for the damping rate in uniform and non-uniform systems. Using simple energy-momentum conservation arguments, we show that in the homogeneous system, the nature of the low energy dispersion in a dipolar Bose gas severely inhibits Landau damping of long wave-length excitations. For a gas with contact and dipolar interactions, the damping rate for phonons tends to decrease with increasing dipolar interactions; for strong dipole-dipole interactions, phonons are virtually undamped over a broad range of temperature. The damping rate for maxon-roton excitations is found to be significantly larger than the damping rate for phonons.

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Stefan S. Natu, Ryan M. Wilson. 2013-10-23. Landau damping in a collisionless dipolar Bose gas. https://doi.org/10.1103/physreva.88.063638

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