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arXiv · 2102.11654

Nonlinear absorption in interacting Rydberg electromagnetically-induced-transparency spectra on two-photon resonance

Annika Tebben·Clément Hainaut·Andre Salzinger·Sebastian Geier·Titus Franz·Thomas Pohl·Martin Gärttner·Gerhard Zürn·Matthias Weidemüller
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Abstract

We experimentally investigate the nonlinear transmission spectrum of coherent light fields propagating through a Rydberg EIT medium with strong atomic interactions. In contrast to previous investigations, which have largely focused on resonant control fields, we explore here the full two-dimensional spectral response of the Rydberg gas. Our measurements confirm previously observed spectral features for a vanishing control-field detuning, but also reveal significant differences on two-photon resonance. In particular, we find qualitative deficiencies of mean-field models and rate-equation simulations as well as a third-order nonlinear susceptibility that accounts for pair-wise interaction effects at low probe-field intensities in describing the nonlinear probe-field response under EIT conditions. Our results suggest that a more complete understanding of Rydberg-EIT and emerging photon interactions requires to go beyond existing simplified models as well as few-photon theories.

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Annika Tebben, Clément Hainaut, Andre Salzinger, Sebastian Geier, Titus Franz, Thomas Pohl, Martin Gärttner, Gerhard Zürn, Matthias Weidemüller. 2021-08-11. Nonlinear absorption in interacting Rydberg electromagnetically-induced-transparency spectra on two-photon resonance. https://doi.org/10.1103/physreva.103.063710

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