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Journal of Applied Physics

Collective state of the Bose gas of interacting dipolar excitons

Vladislav B. Timofeev, А. В. Горбунов

Published Apr 15, 2007• 48 citations
Publisher

Abstract

Experiments connected with dipolar exciton Bose condensation in ring lateral traps are presented. The long-range spatial coherence of condensate along the sample surface is observed and discussed for the first time.
DOI
10.1063/1.2722742

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The phase diagram of Bose-Einstein condensates of dipolar excitons accumulated in lateral electrostatic traps is determined. Spatially periodic luminescence structures of the exciton Bose condensate and their critical dependence on pump level and temperature are observed. Coherence in the dipolar exciton Bose-Einstein condensates is studied by direct measurement of the 1-st and 2-nd order correlators with variations in pump level and temperature. These results are indicative of large-scale coherence of the exciton Bose condensate.
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