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

N. Katz, J. Steinhauer, R. Ozeri, N. Davidson

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.

"Beliaev damping of quasi-particles in a Bose-Einstein condensate ", N. Katz, J. Steinhauer, R. Ozeri, N. Davidson, Phys. Rev. Lett. 89, 220401 (2002). (PDF)

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