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arXiv · 1503.07402

Ghost Branch Photoluminescence From a Polariton Fluid Under Nonresonant Excitation

Maciej Pieczarka·Marcin Syperek·Łukasz Dusanowski·Jan Misiewicz·Fabian Langer·Alfred Forchel·Martin Kamp·Christian Schneider·Sven Höfling·Alexey Kavokin·Grzegorz Sęk
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Abstract

An expanding polariton condensate is investigated under pulsed nonresonant excitation with a small laser pump spot. Far above the condensation threshold we observe a pronounced increase in the dispersion curvature with a subsequent linearization of the spectrum and strong luminescence from a ghost branch orthogonally polarized with respect to the linearly polarized condensate emission. The presence of the ghost branch has been confirmed in time-resolved measurements. The dissipative and nonequilibrium effects in the photoluminescence of polariton condensates and their excitations are discussed.

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Maciej Pieczarka, Marcin Syperek, Łukasz Dusanowski, Jan Misiewicz, Fabian Langer, Alfred Forchel, Martin Kamp, Christian Schneider, Sven Höfling, Alexey Kavokin, Grzegorz Sęk. 2015-10-22. Ghost Branch Photoluminescence From a Polariton Fluid Under Nonresonant Excitation. https://doi.org/10.1103/physrevlett.115.186401

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