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arXiv · 1004.2282

Strongly Enhanced Spin Squeezing via Quantum Control

Collin M. Trail·Poul S. Jessen·Ivan H. Deutsch
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Abstract

We describe a new approach to spin squeezing based on a double-pass Faraday interaction between an optical probe and an optically dense atomic sample. A quantum eraser is used to remove residual spin-probe entanglement, thereby realizing a single-axis twisting unitary map on the collective spin. This interaction can be phase-matched, resulting in exponential enhancement of squeezing. In practice the scaling and peak squeezing depends on decoherence, technical loss, and noise. A simplified model indicates ~10 dB of squeezing should be achievable with current laboratory parameters.

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Collin M. Trail, Poul S. Jessen, Ivan H. Deutsch. 2010-04-13. Strongly Enhanced Spin Squeezing via Quantum Control. https://doi.org/10.1103/physrevlett.105.193602

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