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arXiv · 1607.06530

Protecting and enhancing spin squeezing under decoherence using weak measurement

Xiang-Ping Liao·Man-Sheng Rong·Mao-Fa Fang
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Abstract

We propose an efficient method to protect spin squeezing under the action of amplitude-damping, depolarizing and phase-damping channels based on measurement reversal from weak measurement, and consider an ensemble of N independent spin-1/2 particles with exchange symmetry. We find that spin squeezing can be enhanced greatly under three different decoherence channels and spin-squeezing sudden death (SSSD) can be avoided undergoing amplitude damping and phase-damping channels.

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Xiang-Ping Liao, Man-Sheng Rong, Mao-Fa Fang. 2016-07-26. Protecting and enhancing spin squeezing under decoherence using weak measurement. https://doi.org/10.1088/1612-202x%2Faa6dc7

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