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arXiv · 1309.4842

Quantum Fisher information and spin squeezing in one-axis twisting model

Wei Zhong·Jing Liu·Jian Ma·Xiaoguang Wang
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Abstract

We consider the quantum Fisher information and spin squeezing in one-axis twisting model with a coherent spin state $|θ_{0},ϕ_{0}\rangle$. We analytically discuss the dependence of the two parameters: spin squeezing parameter $ξ^2_{K}$ and the average parameter estimation precision $χ^2$ on the polar angle $θ_{0}$ and the azimuth angle $ϕ_0$. Moreover, we discuss the effects of the collisional dephasing on the dynamics of the two parameters. In this case, the analytical solution of $ξ^2_K$ is also obtained.

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Wei Zhong, Jing Liu, Jian Ma, Xiaoguang Wang. 2014-05-06. Quantum Fisher information and spin squeezing in one-axis twisting model. https://doi.org/10.1088/1674-1056%2F23%2F6%2F060302

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