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arXiv · 2007.01964

Observing spin-squeezed states under spin-exchange collisions for a second

Meng-Zi Huang·Jose Alberto de la Paz·Tommaso Mazzoni·Konstantin Ott·Peter Rosenbusch·Alice Sinatra·Carlos L. Garrido Alzar·Jakob Reichel
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Abstract

Using the platform of a trapped-atom clock on a chip, we observe the time evolution of spin-squeezed hyperfine clock states in ultracold rubidium atoms on previously inaccessible timescales up to 1 s. The spin degree-of-freedom remains squeezed after 0.6 s, which is consistent with the limit imposed by particle loss and is compatible with typical Ramsey times in state-of-the-art microwave clocks. The results also reveal a surprising spin-exchange interaction effect that amplifies the cavity-based spin measurement via a correlation between spin and external degrees of freedom. These results open up perspectives for squeezing-enhanced atomic clocks in a metrologically relevant regime and highlight the importance of spin interactions in real-life applications of spin squeezing.

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Meng-Zi Huang, Jose Alberto de la Paz, Tommaso Mazzoni, Konstantin Ott, Peter Rosenbusch, Alice Sinatra, Carlos L. Garrido Alzar, Jakob Reichel. 2020-07-03. Observing spin-squeezed states under spin-exchange collisions for a second. https://doi.org/10.1103/prxquantum.4.020322

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