噪声环境下基于无噪声线性放大的量子Ziv-Zakai界限相位估计

Quantum Ziv-Zakai Bound Phase Estimation Based on Noiseless Linear Amplification in Noisy Environments

摘要: 本研究针对未知参数可用精度极限的有效寻找问题进行探讨。在量子Ziv-Zakai界限(Quantum Ziv-Zakai bound, QZZB)的框架内，利用无噪声线性放大(Noiseless linear amplification, NLA)技术对初始相干态进行处理，研究在光子损耗和相位扩散的噪声环境下相位估计性能的改善情况。结果显示，通过增加NLA增益因子，可以显著提升QZZB在光子损失和相位扩散情况下的相位估计性能，尤其在严重光子损耗时提升效果更为显著。这些发现对于复杂环境下量子信息处理任务具有重要的指导作用。

Abstract: This paper explores the achievable accuracy limit for estimating unknown parameters. Within the framework of quantum Ziv-Zakai bound (QZZB), the noiseless linear amplification (NLA) technique is applied to process the initial coherent state for enhancing phase estimation performance amid photon loss and phase diffusion. The results demonstrate that increasing the NLA gain factor significantly enhances the QZZB-based phase estimation performance under bothphoton loss and phase diffusion conditions, whith particularly notable improvement in scenarios involving severe photon loss. These findings provide critical guidance for quantum information processing tasks in complex environments.