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arXiv · 2002.02893

Long-lived circular Rydberg states of laser-cooled Rubidium atoms in a cryostat

Tigrane Cantat-Moltrecht·Rodrigo Cortiñas·Brice Ravon·Paul Méhaignerie·Serge Haroche·Jean-Michel Raimond·Maxime Favier·Michel Brune·Clément Sayrin
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Abstract

The exquisite properties of Rydberg levels make them particularly appealing for emerging quantum technologies. The lifetime of low-angular-momentum laser-accessible levels is however limited to a few $100\,μ\mathrm{s}$ by optical transitions and microwave blackbody radiation (BBR) induced transfers at room temperature. A considerable improvement would be obtained with the few $10\,\mathrm{ms}$ lifetime of circular Rydberg levels in a cryogenic environment reducing the BBR temperature. We demonstrate the preparation of long-lived circular Rydberg levels of laser-cooled Rubidium atoms in a cryostat. We observe a $3.7\,\mathrm{ms}$ lifetime for the circular level of principal quantum number $n=52$. By monitoring the transfers between adjacent circular levels, we estimate in situ the microwave BBR temperature to be $(11\pm 2)\,\mathrm{K}$. The measured atomic coherence time ($270\,μ\mathrm{s}$) is limited here only by technical magnetic field fluctuations. This work opens interesting perspectives for quantum simulation and sensing with cold circular Rydberg atoms.

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Tigrane Cantat-Moltrecht, Rodrigo Cortiñas, Brice Ravon, Paul Méhaignerie, Serge Haroche, Jean-Michel Raimond, Maxime Favier, Michel Brune, Clément Sayrin. 2020-03-12. Long-lived circular Rydberg states of laser-cooled Rubidium atoms in a cryostat. https://doi.org/10.1103/physrevresearch.2.022032

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