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arXiv · 1408.1568

Stability of persistent currents in open-dissipative quantum fluids

Abstract

The phenomenon of stable persistent currents is central to the studies of superfluidity in a range of physical systems. While all of the previous theoretical studies of superfluid flows in annular geometries concentrated on conservative systems, here we extend the stability analysis of persistent currents to open-dissipative exciton-polariton superfluids. By considering an exciton-polariton condensate in an optically-induced annular trap, we determine stability conditions for an initially imposed flow with a non-zero orbital angular momentum. We show, theoretically and numerically, that the system can sustain metastable persistent currents in a large parameter region, and describe scenarios of the supercurrent decay due to the dynamical instability.

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Guangyao Li, Michael D. Fraser, Alexander Yakimenko, Elena A. Ostrovskaya. 2014-08-07. Stability of persistent currents in open-dissipative quantum fluids. https://arxiv.org/abs/1408.1568

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