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arXiv · 2102.00229

Coupling light to a nuclear spin gas with a two-photon linewidth of five millihertz

Or Katz·Roy Shaham·Ofer Firstenberg
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Abstract

Nuclear spins of noble gases feature extremely long coherence times but are inaccessible to optical photons. Here we realize a coherent interface between light and noble-gas spins that is mediated by alkali atoms. We demonstrate the optical excitation of the noble-gas spins and observe the coherent back-action on the light in the form of high-contrast two-photon spectra. We report on a record two-photon linewidth of 5$\pm$0.7 mHz (millihertz) above room-temperature, corresponding to a one-minute coherence time. This experiment provides a demonstration of coherent bi-directional coupling between light and noble-gas spins, rendering their long-lived spin coherence accessible for manipulations in the optical domain.

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Or Katz, Roy Shaham, Ofer Firstenberg. 2021-01-30. Coupling light to a nuclear spin gas with a two-photon linewidth of five millihertz. https://doi.org/10.1126/sciadv.abe9164

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