Radiation from accelerated impurities in a Bose–Einstein condensate

Siu A. Chin, Harald Forbert

Alex Retzker, J. I. Cirac, Martin Bodo Plenio +1 more

We propose and study methods for detecting Unruh-like acceleration radiation effects in a Bose-Einstein condensate in a (1+1)-dimensional setup. The Bogoliubov vacuum of a Bose-Einstein condensate is used to simulate a scalar field theory, and accelerated atom dots or optical lattices serve as detectors of phonon radiation due to acceleration effects. In particular, we study the dispersive effects of the Bogoliubov spectrum on the ideal case of exact thermalization. Our results suggest that acceleration radiation effects can be observed using currently accessible experimental methods.

Siu A. Chin, Harald Forbert

When a sizable, hard-sphere-like impurity is placed in a trapped Bose-Einstein condensate, it will create a hole in the condensate wave function. Since it costs more energy to drill a hole at the wave function's maximum (near the trap center) than at its minimum (near the trap edge), the impurity will be expelled from the condensate. This suggests that C-60 molecules freely falling through a condensate of atomic hydrogen may be deflected by a radial acceleration comparable to g. The scattered fullerenes would then form a characteristic banded density pattern outside of the trap. The detection of these deflected molecules can be used to identify the onset of Bose-Einstein condensation.

S. Inouye, A. P. Chikkatur, Dan Stamper-Kurn +3 more

Jun Suzuki

A model for classical impurities moving in Bose-Einstein Condensate (BEC) is proposed in the framework of quantum field theory and is solved within the Bogoliubov approximation at zero temperature. Several formulae are obtained for physical quantities such as the occupation number, the dissipation, the free energy, and the depletion. To illustrate this model two examples are studied; an impurity moving with i) a constant velocity and ii) a constant acceleration. Landau's criterion for energy dissipation accompanying the motion of impurities due to creation of quasi-particles in a superfluid, which was proposed on the basis of purely phenomenological argument, is obtained in the frame work of an exact quantum mechanical model.

Chikkatur, Gorlitz, Dan Stamper-Kurn +3 more