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arXiv · 1512.00241

The precision of parameter estimation for dephasing model under squeezed reservoir

Shao-xiong Wu·Chang-shui Yu
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Abstract

We study the precision of parameter estimation for dephasing model under squeezed environment. We analytically calculate the dephasing factor $γ(t)$ and obtain the analytic quantum Fisher information (QFI) for the amplitude parameter $α$ and the phase parameter $ϕ$. It is shown that the QFI for the amplitude parameter $α$ is invariant in the whole process, while the QFI for the phase parameter $ϕ$ strongly depends on the reservoir squeezing. It is shown that the QFI can be enhanced for appropriate squeeze parameters $r$ and $θ$. Finally, we also investigate the effect of temperature on the QFI.

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Shao-xiong Wu, Chang-shui Yu. 2018-02-25. The precision of parameter estimation for dephasing model under squeezed reservoir. https://doi.org/10.1007/s10773-016-3262-x

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