Conditions for one-dimensional supersonic flow of quantum gases

TL;DR

This paper establishes the conditions under which quantum gases in Bose-Einstein condensates can achieve one-dimensional supersonic flow, enabling laboratory analogs of black hole horizons and Hawking radiation detection.

Contribution

It provides a detailed analysis of the external potential parameters necessary for inducing supersonic flow and calculating Hawking temperature in realistic condensate waveguides.

Findings

Supersonic transition occurs at the potential maximum.

Hawking temperature depends on the potential curvature.

Conditions for experimental realization are specified.

Abstract

One can use transsonic Bose-Einstein condensates of alkali atoms to establish the laboratory analog of the event horizon and to measure the acoustic version of Hawking radiation. We determine the conditions for supersonic flow and the Hawking temperature for realistic condensates on waveguides where an external potential plays the role of a supersonic nozzle. The transition to supersonic speed occurs at the potential maximum and the Hawking temperature is entirely determined by the curvature of the potential.