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arXiv · 0812.4863

Polarization-based Light-Atom Quantum Interface with an All-optical Trap

Marcin Kubasik·Marco Koschorreck·Mario Napolitano·Sebastián R. de Echaniz·Herbert Crepaz·Jürgen Eschner·Eugene S. Polzik·Morgan W. Mitchell
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Abstract

We describe the implementation of a system for studying light-matter interactions using an ensemble of $10^6$ cold rubidium 87 atoms, trapped in a single-beam optical dipole trap. In this configuration the elongated shape of the atomic cloud increases the strength of the collective light-atom coupling. Trapping all-optically allows for long storage times in a low decoherence environment. We are able to perform several thousands of measurements on one atomic ensemble with little destruction. We report results on paramagnetic Faraday rotations from a macroscopically polarized atomic ensemble. Our results confirm that strong light-atom coupling is achievable in this system which makes it attractive for single-pass quantum information protocols.

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Marcin Kubasik, Marco Koschorreck, Mario Napolitano, Sebastián R. de Echaniz, Herbert Crepaz, Jürgen Eschner, Eugene S. Polzik, Morgan W. Mitchell. 2008-12-29. Polarization-based Light-Atom Quantum Interface with an All-optical Trap. https://doi.org/10.1103/physreva.79.043815

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