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

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.

12 pages, 6 figures

References in corpus (7)

• Nonlinear atom interferometer surpasses classical precision limit
• Precision Measurement of the Newtonian Gravitational Constant Using Cold Atoms
• Progress in Atomic Fountains at LNE-SYRTE
• Tackling Systematic Errors in Quantum Logic Gates with Composite Rotations
• Near-Unitary Spin Squeezing in ${}^{171}$Yb
• Stability of a trapped atom clock on a chip
• Dynamical generation of spin squeezing in ultra-cold dipolar molecules

Cited by in corpus (4)

• Squeezed Ground States in a Spin-1 Bose-Einstein Condensate
• Analysis of spin-squeezing generation in cavity-coupled atomic ensembles with continuous measurements
• A cavity-microscope for micrometer-scale control of atom-photon interactions
• Protecting spin squeezing from decoherence