标题： 一般去相位存在下的量子费舍尔信息的上界 显示英文标题

标题： Upper bounds on the quantum Fisher Information in the presence of general dephasing

摘要： 我们推导了在存在任意相关高斯去相位的情况下，干涉仪中具有$N$个子系统的量子费舍尔信息的上界，例如两能级原子或高斯模式，包括独立和集体去相位。 所推导的上界使我们能够分析当$N\rightarrow\infty$时费舍尔信息的渐近行为。 去相位会向子系统动力学引入随机相位，这会降低干涉仪中相位差$\phi$估计的精度。 所提出的方法使用随机相位的贝叶斯估计，并通过计算它们的加权算术平均值来消除去相位噪声，这对应于干涉仪中估计的相位$\phi$。 显示英文摘要

摘要： We derive upper bounds on the quantum Fisher information in interferometry with $N$ subsystems, e.g. two-level atoms or Gaussian modes, in the presence of arbitrarily correlated Gaussian dephasing including independent and collective dephasing. The derived upper bound enables us to analyse the Fisher information asymptotic behaviour when $N\rightarrow\infty$. Dephasing introduces random phases to subsystems dynamics, which lowers the precision of estimating the phase difference $\phi$ in an interferometer. The method presented uses Bayesian estimation of the random phases and eliminates dephasing noise by calculating their weighted arithmetic mean, which correponds to the phase $\phi$ estimated in interferometry.