Density correlations from analogue Hawking radiation in the presence of atom losses

Abstract

The sonic analogue of Hawking radiation can now be experimentally recreated in Bose-Einstein Condensates that contain an acoustic black hole. In these experiments the signal strength and analogue Hawking temperature increase for denser condensates, which however also suffer increased atom losses from inelastic collisions. To determine how these affect analogue Hawking radiation, we numerically simulate creation of the latter in a Bose-Einstein Condensate in the presence of atomic losses. In particular we explore modifications of density-density correlations through which the radiation has been analyzed so far. We find that losses increase the contrast of the correlation signal, which we attribute to heating that in turn leads to a component of stimulated radiation in addition to the spontaneous one. Another indirect consequence is the modification of the white hole instability pattern.