Superfluidity and Critical Velocities in Nonequilibrium Bose-Einstein Condensates

Journal Article · Fri Jul 09 00:00:00 EDT 2010 · Physical Review Letters

DOI:https://doi.org/10.1103/PHYSREVLETT.105.020602· OSTI ID:21410895

Wouters, Michiel ^[1]; Carusotto, Iacopo ^[2]

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1. Institute of Theoretical Physics, Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland)
2. INO-CNR BEC Center and Dipartimento di Fisica, Universita di Trento, I-38123 Povo (Italy)

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.

• OSTI ID: 21410895
• Journal Information: Physical Review Letters, Vol. 105, Issue 2; Other Information: DOI: 10.1103/PhysRevLett.105.020602; (c) 2010 The American Physical Society; ISSN 0031-9007
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BOSE-EINSTEIN CONDENSATION
CRITICAL VELOCITY
DENSITY
EXCITATION
EXCITONS
MEAN-FIELD THEORY
NUCLEAR PUMPING
POLARONS
SEMICONDUCTOR MATERIALS
SUPERFLUIDITY
WAVE FUNCTIONS
ENERGY-LEVEL TRANSITIONS
FUNCTIONS
MATERIALS
PHYSICAL PROPERTIES
PUMPING
QUASI PARTICLES
VELOCITY