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Bose-Einstein condensate of two-dimensional excitons in a ring: Necklace-like modulation of order parameter

S. -R. Eric Yang·Q-Han Park·J. Yeo
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Abstract

We have studied theoretically the Bose-Einstein condensation (BEC) of two-dimensional excitons in a ring with small random width variation. We derive a nonlinear Gross-Pitaevkii equation (GPE) for such a condensate. Our numerical solution of the ground state of the GPE displays a necklace-like structure in the presence of small random variation of ring width. This is a consequence of the interplay between random potential and the nonlinear repulsive term of the GPE. Our result suggests that the formation of ring and necklace-like structures observed recently in the photoluminescence of quantum wells may be stable even in the BEC phase.

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S. -R. Eric Yang, Q-Han Park, J. Yeo. 2003-12-15. Bose-Einstein condensate of two-dimensional excitons in a ring: Necklace-like modulation of order parameter. https://arxiv.org/abs/cond-mat/0312354

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