论文标题
评估在嘈杂环境中绑定的量子Ziv-Zakai
Evaluating the quantum Ziv-Zakai bound in noisy environments
论文作者
论文摘要
在高度非高斯政权中，Quantum Ziv-Zakai Bound（QZZB）在可用的精确度上提供了一个下限，这表明与量子Cramér-Rao结合相比，性能更好。但是，在不应用Tsang提出的某些近似值的情况下，评估嘈杂环境对QZZB的影响[Phys。莱特牧师。 108，230401（2012）]仍然是一个困难的挑战。 In this paper, we not only derive the general form of the QZZB with the photon loss and the phase diffusion by invoking the technique of integration within an ordered product of operators, but also show its estimation performance for several different Gaussian resources, such as a coherent state (CS), a single-mode squeezed vacuum state (SMSVS) and a two-mode squeezed vacuum state (TMSVS).我们的结果表明，与SMSV和TMSV相比，CS的QZZB始终显示出在光子损失环境下的估计性能更好。更有趣的是，对于相扩散环境，QZZB对TMSV的估计性能比在各种相位扩散强度范围内的CS更好。我们的发现将为研究嘈杂的量子参数估计提供有用的指导。
In the highly non-Gaussian regime, the quantum Ziv-Zakai bound (QZZB) provides a lower bound on the available precision, demonstrating the better performance compared with the quantum Cramér-Rao bound. However, evaluating the impact of a noisy environment on the QZZB without applying certain approximations proposed by Tsang [Phys. Rev. Lett. 108, 230401 (2012)] remains a difficult challenge. In this paper, we not only derive the general form of the QZZB with the photon loss and the phase diffusion by invoking the technique of integration within an ordered product of operators, but also show its estimation performance for several different Gaussian resources, such as a coherent state (CS), a single-mode squeezed vacuum state (SMSVS) and a two-mode squeezed vacuum state (TMSVS). Our results indicate that compared with the SMSVS and the TMSVS, the QZZB for the CS always shows the better estimation performance under the photon-loss environment. More interestingly, for the phase-diffusion environment, the estimation performance of the QZZB for the TMSVS can be better than that for the CS throughout a wide range of phase-diffusion strength. Our findings will provide a useful guidance for investigating the noisy quantum parameter estimation.
