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arXiv · 0803.3239

Theory of Bose-Einstein condensation and superfluidity of two-dimensional polaritons in an in-plane harmonic potential

Oleg L. Berman·Yurii E. Lozovik·David W. Snoke
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Abstract

Recent experiments have shown that it is possible to create an in-plane harmonic potential trap for a two-dimensional (2D) gas of exciton-polaritons in a microcavity structure, and evidence has been reported of Bose-Einstein condensation of polaritons accumulated in this type of trap. We present here the theory of Bose-Einstein condensation (BEC) and superfluidity of the exciton polaritons in a harmonic potential trap. Along the way, we determine a general method for defining the superfluid fraction in a 2D trap, in terms of angular momentum representation. We show that in the continuum limit, as the trap becomes shallower the superfluid fraction approaches the 2D Kosterlitz-Thouless limit, while the condensate fraction approaches zero, as expected.

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Oleg L. Berman, Yurii E. Lozovik, David W. Snoke. 2008-03-21. Theory of Bose-Einstein condensation and superfluidity of two-dimensional polaritons in an in-plane harmonic potential. https://doi.org/10.1103/physrevb.77.155317

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