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arXiv · 1911.09617

Single-Particle Decoherence Can Improve Spin-Squeezing Generated In Collective Dynamics

K. Tucker·D. Barberena·R. J. Lewis-Swan·J. K. Thompson·J. G. Restrepo·A. M. Rey
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Abstract

We study the generation of spin-squeezing in arrays of long-lived dipoles subject to collective emission, coherent drive, elastic interactions, and spontaneous emission. Counter-intuitively, it is found that the introduction of spontaneous emission leads to an enhancement of the achievable spin-squeezing, relative to that which emerges in the steady-state of the purely collective dynamics for the same model parameters. This behavior is connected to the dynamical self-tuning of the system through a dissipative phase transition that is present in the collective system alone. Our findings will be applicable to next-generation quantum sensors harnessing correlated quantum matter, including cavity-QED and trapped ion systems.

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K. Tucker, D. Barberena, R. J. Lewis-Swan, J. K. Thompson, J. G. Restrepo, A. M. Rey. 2019-12-13. Single-Particle Decoherence Can Improve Spin-Squeezing Generated In Collective Dynamics. https://doi.org/10.1103/physreva.102.051701

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