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Beliaev damping of quasi-particles in a Bose-Einstein condensate

N. Katz·J. Steinhauer·R. Ozeri·N. Davidson
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Abstract

We report a measurement of the suppression of collisions of quasi-particles with ground state atoms within a Bose-Einstein condensate at low momentum. These collisions correspond to Beliaev damping of the excitations, in the previously unexplored regime of the continuous quasi-particle energy spectrum. We use a hydrodynamic simulation of the expansion dynamics, with the Beliaev damping cross-section, in order to confirm the assumptions of our analysis.

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N. Katz, J. Steinhauer, R. Ozeri, N. Davidson. 2002-06-13. Beliaev damping of quasi-particles in a Bose-Einstein condensate. https://doi.org/10.1103/physrevlett.89.220401

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