arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2004.05831quant-ph
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压缩热态下的量子增强光学相位估计

Quantum enhanced optical phase estimation with a squeezed thermal state

Juan Yu, Yue Qin, Jinliang Qin, Hong Wang, Zhihui Yan, Xiaojun Jia, Kunchi Peng

摘要:

由于非经典光态的应用,量子相位估计协议可以提供一种精度优于标准量子极限(SQL)的相移测量方法。压缩真空态是量子相位估计的敏感源,它的一次正交方差小于相应的SQL,压缩真空态的性质直接影响量子相位估计的精度。本文详细分析了压缩态的纯度和压缩能级对量子相位估计精度的影响。计算了压缩热态下的最大测量精度,实验结果与理论分析一致。研究还发现,相位估计间隔$Δθ$超出SQL的宽度与压缩态的纯度有关。

英文摘要:

Quantum phase estimation protocols can provide a measuring method of phase shift with precision superior to standard quantum limit (SQL) due to the application of a nonclassical state of light. A squeezed vacuum state, whose variance in one quadrature is lower than the corresponding SQL, has been pointed out a sensitive resource for quantum phase estimation and the estimation accuracy is directly influenced by the properties of the squeezed state. Here we detailedly analyze the influence of the purity and squeezing level of the squeezed state on the accuracy of quantum phase estimation. The maximum precision that can be achieved for a squeezed thermal state is evaluated, and the experimental results are in agreement with the theoretical analyses. It is also found that the width of the phase estimation interval $Δθ$ beyond SQL is correlated with the purity of the squeezed state.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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