Damping in dilute Bose gases: a mean-field approach
نویسنده
چکیده
Damping in a dilute Bose gas is investigated using a mean-field approximation which describes the coupled oscillations of condensate and non-condensate atoms in the collisionless regime. Explicit results for both Landau and Beliaev damping rates are given for non-uniform gases. In the case of uniform systems we obtain results for the damping of phonons both at zero and finite temperature. The isothermal compressibility of a uniform gas is also discussed. 02.70.Lq, 67.40.Db Typeset using REVTEX 1
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