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Macroscopically ordered state in exciton system

L. V. Butov·A. C. Gossard·D. S. Chemla
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Abstract

Macroscopically ordered arrays of vortices in quantum liquids, such as superconductors, He-II, and atom Bose-Einstein Condensates (BEC), demonstrate macroscopic coherence in flowing superfluids [1-4]. Despite of the rich variety of systems where quantum liquids reveal macroscopic ordering, experimental observation of a macroscopically ordered electronic state in semiconductors has remained a challenging unexplored problem. A system of excitons is a promising candidate for the realization of macroscopic ordering in a quantum liquid in semiconductors. An exciton is a bound pair of an electron and a hole. At low densities, it is a Bose quasi-particle. At low temperatures, of the order of a few Kelvins, excitons can form a quantum liquid, i.e., a statistically degenerate Bose gas and eventually BEC [5-9]. Here, we report the experimental observation of a macroscopically ordered state in an exciton system.

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L. V. Butov, A. C. Gossard, D. S. Chemla. 2002-04-22. Macroscopically ordered state in exciton system. https://doi.org/10.1038/nature00943

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