Superfluidity and Critical Velocities in Nonequilibrium Bose-Einstein Condensates

We theoretically study the superfluidity properties of a nonequilibrium Bose-Einstein condensate of exciton polaritons in a semiconductor microcavity under incoherent pumping. The dynamics of the condensate is described at mean-field level in terms of a generalized Gross-Pitaevskii equation. The drag force on a small moving object and the onset of fringes in the density profile are shown to have a sharp threshold as a function of the velocity; a generalized Landau criterion is developed to explain this behavior in terms of the dispersion of elementary excitations. Metastability of supercurrents in multiply-connected geometries is shown to persist up to higher flow speeds.


Published in:
Physical Review Letters, 105, 020602
Year:
2010
Keywords:
Laboratories:




 Record created 2011-12-16, last modified 2018-03-17


Rate this document:

Rate this document:
1
2
3
 
(Not yet reviewed)