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arXiv · 1401.0756

Algebraic order and the Berezinskii-Kosterlitz-Thouless transition in an exciton-polariton gas

Wolfgang H. Nitsche·Na Young Kim·Georgios Roumpos·Christian Schneider·Martin Kamp·Sven Hoefling·Alfred Forchel·Yoshihisa Yamamoto
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Abstract

We observe quasi-long range coherence in a two-dimensional condensate of exciton-polaritons. Our measurements are the first to confirm that the spatial correlation algebraically decays with a slow power-law, whose exponent quantitatively behaves as predicted by the Berezinskii-Kosterlitz-Thouless theory. The exciton-polaritons are created by non-resonant optical pumping of a micro-cavity sample with embedded GaAs quantum-wells at liquid helium temperature. Michelson interference is used to measure the coherence of the photons emitted by decaying exciton-polaritons.

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Wolfgang H. Nitsche, Na Young Kim, Georgios Roumpos, Christian Schneider, Martin Kamp, Sven Hoefling, Alfred Forchel, Yoshihisa Yamamoto. 2014-01-04. Algebraic order and the Berezinskii-Kosterlitz-Thouless transition in an exciton-polariton gas. https://doi.org/10.1103/physrevb.90.205430

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