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arXiv · 1109.3752

Unitary Cavity Spin Squeezing by Quantum Erasure

Ian D. Leroux·Monika H. Schleier-Smith·Hao Zhang·Vladan Vuletić
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Abstract

Deterministic light-induced spin squeezing in an atomic gas is limited by photon shot noise or, equivalently, by atomic state information escaping with the light field mediating the effective atom-atom interaction. We show theoretically that the performance of cavity spin squeezing [M.H. Schleier-Smith, I.D. Leroux, and V. Vuletić, Phys. Rev. A 81, 021804(R) (2010)] can be substantially improved by erasing the light-atom entanglement, and propose several methods for doing so. Accounting for light scattering into free space, quantum erasure improves the scaling of cavity squeezing from S^(-1/2) to S^(-2/3), where S is the total atomic spin.

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Ian D. Leroux, Monika H. Schleier-Smith, Hao Zhang, Vladan Vuletić. 2012-01-05. Unitary Cavity Spin Squeezing by Quantum Erasure. https://doi.org/10.1103/physreva.85.013803

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