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arXiv · 2207.12293

Pure dephasing induced single-photon parametric down-conversion in an ultrastrong coupled plasmon-exciton system

Ruben Pompe·Matthias Hensen·Matthew Otten·Stephen K. Gray·Walter Pfeiffer
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Abstract

In coupled quantum systems pure dephasing mechanisms acting on one constituent of the hybrid system break symmetry and enable optical transitions which are forbidden in the non-coupled system, i.e., the pure dephasing bath opens a cascaded dissipation pathway. Here we show that this mechanism enables single-photon induced parametric down-conversion in an ultrastrongly coupled plasmon-exciton system. Fast pure dephasing of the exciton is shown to support photon pair generation as the dominant energy relaxation pathway.

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Ruben Pompe, Matthias Hensen, Matthew Otten, Stephen K. Gray, Walter Pfeiffer. 2022-07-25. Pure dephasing induced single-photon parametric down-conversion in an ultrastrong coupled plasmon-exciton system. https://arxiv.org/abs/2207.12293

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