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arXiv · 2501.07899

Excitonic oscillator-strength saturation dominates polariton-polariton interactions

Maxime Richard·Irénée Frérot·Sylvain Ravets·Jacqueline Bloch·Carlos Anton-Solanas·Ferdinand Claude·Yueguang Zhou·Martina Morassi·Aristide Lemaître·Iacopo Carusotto·and Anna Minguzzi
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Abstract

Exciton-polaritons in semiconductor microcavities exhibit large two-body interactions that, thanks to ever refined nanotechnology techniques, are getting closer and closer to the quantum regime where single-photon nonlinearities start being relevant. To foster additional progress in this direction, in this work we experimentally investigate the microscopic mechanism driving polariton-polariton interactions. We measure the dispersion relation of the collective excitations that are thermally generated on top of a coherent fluid of interacting lower-polaritons. By comparing the measurements with the Bogoliubov theory over both the lower and upper polariton branches simultaneously, we find that polariton-polariton interactions stem dominantly from a mechanism of saturation of the exciton oscillator strength.

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Maxime Richard, Irénée Frérot, Sylvain Ravets, Jacqueline Bloch, Carlos Anton-Solanas, Ferdinand Claude, Yueguang Zhou, Martina Morassi, Aristide Lemaître, Iacopo Carusotto, and Anna Minguzzi. 2025-01-14. Excitonic oscillator-strength saturation dominates polariton-polariton interactions. https://arxiv.org/abs/2501.07899

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