AI 中文总结
本研究提出用光参量放大多模纠缠态实现量子分布式传感，该态在大增益 OPA 下对损耗鲁棒，可提升量子传感灵敏度，为实际大规模量子计量提供了方法。
AI 中文摘要
量子计量学利用量子态实现超越经典极限的估计灵敏度。在连续变量（CV）领域，压缩态已被用于实现确定性量子传感，但该态的量子计量灵敏度会受损耗或探测效率低下的显著影响，这限制了其应用。本研究提出利用从压缩态产生的光参量放大多模纠缠态实现量子分布式传感。研究发现，当引入大增益光参量放大（OPA）时，灵敏度对损耗或探测效率低下具有鲁棒性，其中采用双模爱因斯坦-波多尔斯基-罗森（EPR）纠缠态和四模 cluster 态进行分析。在几乎所有损耗场景下，与未使用 OPA 的情况相比，量子灵敏度都得到了大幅提升。针对两种态计算量子费舍尔矩阵以获取最优界，并与本方案进行对比，结果表明，即使使用较小或中等的 OPA 增益，与传统方案相比也可改善量子传感性能。还将这些态与相应的单模压缩态进行对比，明确了纠缠态表现更优的参数范围。本研究为在存在损耗或探测效率低下的实际应用中实现大规模量子计量提供了一种方法。
英文摘要
Quantum metrology exploits quantum states to achieve an estimation sensitivity beyond classical limits. In the continuous-variable (CV) regime, the squeezed state has been used to implement deterministic quantum sensing, but the quantum metrology sensitivity of this state is significantly affected by losses or detection inefficiencies, which restrict its applications. In this work, quantum distributed sensing is proposed using optical parametric amplified multimode entanglement generated from squeezed states. It is found that the sensitivity is robust to loss or detection inefficiency when large-gain optical parametric amplification (OPA) is introduced, where a two-mode Einstein--Podolsky--Rosen-entangled state and a four-mode cluster state are exploited for analysis. The quantum sensitivity is greatly improved compared to that without OPA in almost all loss scenarios. The quantum Fisher matrix is calculated for both states to obtain the optimal bound in comparison with our scheme, and it is found that even with a small or moderate OPA gain, quantum sensing can be improved compared with the traditional scheme. The states are also compared with corresponding single-mode squeezed states, finding the parameter ranges where entangled states perform better. This study provides a method for realizing large-scale quantum metrology in real-world applications despite losses or detection inefficiencies.
CommentsPublished in Sensors 2026, 26(17), 5547; https://doi.org/10.3390/s26175547 (registering DOI)
