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arXiv · 1906.05151

Observation of a large, resonant, cross-Kerr nonlinearity in a free-space Rydberg medium

Josiah Sinclair·Daniela Angulo·Noah Lupu-Gladstein·Kent Bonsma-Fisher·Aephraim M. Steinberg
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Abstract

We report the experimental observation of a cross-Kerr nonlinearity in a free-space medium based on resonantly-excited, interacting Rydberg atoms and electromagnetically induced transparency. The nonlinearity is used to implement cross-phase modulation between two optical pulses. The nonlinear phase written onto the probe pulse is measured to be as large as $8$ mrad per nW of signal power, corresponding to a $\chi^{(3)}$ of $10^{-8}\textrm{m}^2/\textrm{V}^2$. Potential applications range from optical quantum information processing to quantum non-demolition measurement of photon number.

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Josiah Sinclair, Daniela Angulo, Noah Lupu-Gladstein, Kent Bonsma-Fisher, Aephraim M. Steinberg. 2019-06-12. Observation of a large, resonant, cross-Kerr nonlinearity in a free-space Rydberg medium. https://doi.org/10.1103/physrevresearch.1.033193

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