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arXiv · 0904.0496

Spin squeezing in a generalized one-axis twisting model

Guang-Ri Jin·Yong-Chun Liu·Wu-Ming Liu
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Abstract

We investigate the dependence of spin squeezing on the polar angle of the initial coherent spin state $|θ_0, ϕ_0>$ in a generalized one-axis twisting model, where the detuning $δ$ is taken into account. We show explicitly that regardless of $δ$ and $ϕ_0$, previous results of the ideal one-axis twisting is recovered as long as $θ_0=π/2$. For a small departure of $θ_0$ from $π/2$, however, the achievable variance $(V_{-})_{\min}\sim N^{2/3}$, larger than the ideal case $N^{1/3}$. We also find that the maximal-squeezing time $t_{\min}$ scales as $N^{-5/6}$. Analytic expressions of $(V_{-})_{\min}$ and $t_{\min}$ are presented, which agree with numerical simulations.

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Guang-Ri Jin, Yong-Chun Liu, Wu-Ming Liu. 2009-06-27. Spin squeezing in a generalized one-axis twisting model. https://doi.org/10.1088/1367-2630/11/7/073049

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