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arXiv · 0801.1103

Berry Phase Effect on Exciton Transport and Bose Einstein Condensate

Wang Yao·Qian Niu
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Abstract

With exciton lifetime much extended in semiconductor quantum-well structures, their transport and Bose-Einstein condensation become a focus of research in recent years. We reveal a momentum-space gauge field in the exciton center-of-mass dynamics due to Berry phase effects. We predict spin-dependent topological transport of the excitons analogous to the anomalous Hall and Nernst effects for electrons. We also predict spin-dependent circulation of a trapped exciton gas and instability in an exciton condensate in favor of vortex formation.

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Wang Yao, Qian Niu. 2008-07-28. Berry Phase Effect on Exciton Transport and Bose Einstein Condensate. https://doi.org/10.1103/physrevlett.101.106401

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