基于相位压缩态的到达角估计  

Angle of Arrival Estimation via Entangled State

作　　者：孙小聪 田亚莉 宫廷 周月婷 郭古青 和小虎[1] 邱选兵[1] 李传亮[1] SUN Xiao-congt;TIAN Ya-li;GONG Ting;ZHOU Yue-ting;GUO Gu-qing;HE Xiao-hu;QIU Xuan-bing;LI Chuan-liang(Shanxi Province Engineering Research Center of Precision Measurement and Online Detection Equipment,Shanxi Center of Technology Innovation for Light Manipulations and Applications,School of Applied Science,Taiyuan University of Science and Technology,Taiyuan 030024,China)

机构地区：[1]太原科技大学应用科学学院,山西省精密测量与在线检测装备工程研究中心,山西省光场调控与融合应用技术创新中心,山西太原030024

出　　处：《量子光学学报》2024年第2期38-44,共7页Journal of Quantum Optics

基　　金：国家自然科学基金(U1810129,52076145,12304403);山西省留学人员科技活动项目(20230031);山西省省筹资金资助回国留学人员科研资助项目(2023-151);山西省基础研究计划(202203021222204,202303021212224);太原科技大学科研启动基金(20222124,20232035)。

摘　　要：到达角估计作为高精度追踪的关键光学技术,在目标定位、量子测距以及相控阵雷达等领域中有着重要应用。本文提出一种基于相位压缩态的到达角估计协议,采用中心波长为1064 nm的连续固体激光光源、光学参量振荡器及可变分束器,实现最高纠缠度为(6.1±0.2)dB的纠缠态光场制备。通过调控传感节点的调制相位,实现对两个传感节点0~2π相位的精准扫描,从而可以实现突破散粒噪声极限的到达角估计。与经典协议相比,这一协议可以将到达角估计的噪声起伏抑制至散粒噪声基准以下至少5.9 dB,使得到达角精度提高74.1%以上。这一协议有望将相位估计的精度提高至突破散粒噪声极限,为更高精度的空间定位及量子测距技术提供理论和实验基础。Objective As the primary tool for high-precision phase measurement,optical phase sensing has an important application in fields such as target tracking and phased-array radar.Currently,phase sensing primarily relies on distributed quantum sensing protocols to achieve high-precision phase measurement across multiple sensing nodes.Research indicates that utilizing entangled state networks can further improve phase estimation accuracy,reaching measurement sensitivities beyond the shotnoise limit.However,as the number of sensing nodes increases,system losses also increase,leading to a decrease in the precision of optical phase sensing.This becomes a major factor constraining the practical application of quantum sensing.To investigate the potential application of optical phase sensing with fewer nodes,exploration of the angle of arrival (Ao A) in dual-node optical sensing is conducted.Method This paper presents an Ao A estimation protocol based on phase squeezed states.Ao A estimation is transformed into a phase difference estimation problem between two sensing nodes.By deriving the phase difference between two sensing nodes under the beam splitter model,it is found that the measurement accuracy of phase difference is not only limited by the squeezing degree of the phase squeezed state,but also related to the vacuum f luctuations introduced by the beam splitter network.To explore the application of Ao A in dual-node optical sensing,an experimental setup for Ao A estimation based on phase squeezed states is constructed.The preparation of phase squeezed state is carried out using an optical parametric oscillator (OPO).The OPO adopts a single-resonator structure,allowing the 532 nm pump light to pass through the cavity twice and the 1 064 nm fundamental light to resonate inside the cavity.To achieve stable output of phase squeezed state,the OPO should operate in an amplification state.Therefore,the Pound-Drever-Hall (PDH) locking technique is employed to lock the relative phase between the seed light and the pump light.I

关 键 词：光学参量振荡 纠缠态光场 相位估计 

分 类 号：O431.2[机械工程—光学工程]