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arXiv · 1512.08480

Rydberg-induced optical nonlinearities from a cold atomic ensemble trapped inside a cavity

Rajiv Boddeda·Imam Usmani·Erwan Bimbard·Andrey Grankin·Alexei Ourjoumtsev·Etienne Brion·Philippe Grangier
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Abstract

We experimentally characterize the optical nonlinear response of a cold atomic medium placed inside an optical cavity, and excited to Rydberg states. The excitation to S and D Rydberg levels is carried out via a two-photon transition in an EIT (electromagnetically induced transparency) configuration, with a weak (red) probe beam on the lower transition, and a strong (blue) coupling beam on the upper transition. The observed optical nonlinearities induced by S states for the probe beam can be explained using a semi-classical model with van der Waals' interactions. For the D states, it appears necessary to take into account a dynamical decay of Rydberg excitations into a long-lived dark state. We show that the measured nonlinearities can be explained by using a Rydberg bubble model with a dynamical decay.

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Rajiv Boddeda, Imam Usmani, Erwan Bimbard, Andrey Grankin, Alexei Ourjoumtsev, Etienne Brion, Philippe Grangier. 2016-02-21. Rydberg-induced optical nonlinearities from a cold atomic ensemble trapped inside a cavity. https://doi.org/10.1088/0953-4075%2F49%2F8%2F084005

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