Quantum-enhanced interferometry with unbalanced entangled coherent states  

作　　者：Jun Tang Zi-Hang Du Wei Zhong Lan Zhou Yu-Bo Sheng 汤俊;堵子航;钟伟;周澜;盛宇波

机构地区：[1]Institute of Quantum Information and Technology,Nanjing University of Posts and Telecommunications,Nanjing 210003,China [2]School of Science,Nanjing University of Posts and Telecommunications,Nanjing 210003,China [3]College of Electronic and Optical Engineering and College of Flexible Electronics(Future Technology),Nanjing University of Posts and Telecommunications,Nanjing 210003,China

出　　处：《Chinese Physics B》2025年第2期54-62,共9页中国物理B(英文版)

基　　金：supported by the National Natural Science Foundation of China (Grant No. 12005106);support from the National Natural Science Foundation of China (Grant No. 11974189);support from the National Natural Science Foundation of China (Grant No. 12175106);the Postgraduate Research and Practice Innovation Program of Jiangsu Province (Grant No. JSCX23-0260)。

摘　　要：We propose a quantum-enhanced metrological scheme utilizing unbalanced entangled coherent states(ECSs) generated by passing a coherent state and a coherent state superposition through an unbalanced beam splitter(BS). We identify the optimal phase sensitivity of this scheme by maximizing the quantum Fisher information(QFI) with respect to the BS transmission ratio. Our scheme outperforms the conventional scheme with a balanced BS, particularly in the presence of single-mode photon loss. Notably, our scheme retains quantum advantage in phase sensitivity in the limit of high photon intensity, where the balanced scheme offers no advantage over the classical strategy.

关 键 词：quantum-enhanced interferometry entangled coherent state quantum Fisher information 

分 类 号：O413[理学—理论物理]