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arXiv:2202.12338 · Physical Review Letters

Long-Lived Squeezed Ground States in a Quantum Spin Ensemble

Lin Xin, Maryrose Barrios, Julia T. Cohen, Michael Chapman

Published Sep 29, 2023• 15 citations
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Abstract

We generate spin squeezed ground states in an atomic spin-1 Bose-Einstein condensate tuned near the quantum-critical point separating the different spin phases of the interacting ensemble using a novel nonadiabatic technique. In contrast to typical nonequilibrium methods for preparing atomic squeezed states by quenching through a quantum phase transition, squeezed ground states are time stationary with a constant quadrature squeezing angle. A squeezed ground state with 6-8 dB of squeezing and a constant squeezing angle is demonstrated. The long-term evolution of the squeezed ground state is measured and shows gradual decrease in the degree of squeezing over 2 s that is well modeled by a slow tuning of the Hamiltonian due to the loss of atomic density. Interestingly, modeling the gradual decrease does not require additional spin decoherence models despite a loss of 75% of the atoms.

DOI
10.1103/physrevlett.131.133402

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