An acoustic analog to the dynamical Casimir effect in a Bose-Einstein condensate

Jean-Christophe Jaskula (1) , Guthrie B. Partridge (1) , Marie Bonneau (1) , Raphaël Lopes (1) , Josselin Ruaudel (1) , Denis Boiron (1) , Christoph I Westbrook (1)

1 Laboratoire Charles Fabry / Optique atomique

We have realized an acoustic analog to the Dynamical Casimir effect. The density of a trapped Bose-Einstein condensate is modulated by changing the trap stiffness. We observe the creation of correlated excitations with equal and opposite momenta, and show that for a well defined modulation frequency, the frequency of the excitations is half that of the trap modulation frequency.

Keywords: quantum gases; phonons; dynamical Casimir effect

Domains: Quantum Gases [cond-mat.quant-gas]; Optics [physics.optics]

Jean-Christophe Jaskula, Guthrie B. Partridge, Marie Bonneau, Raphaël Lopes, Josselin Ruaudel, et al.. An acoustic analog to the dynamical Casimir effect in a Bose-Einstein condensate. Physical Review Letters, 2012, 109, pp.220401. ⟨10.1103/PhysRevLett.109.220401⟩. ⟨hal-00714837v2⟩