摘要
研究耦合于一维波导的巨原子的单参数和双参数量子Fisher信息动力学。详细分析了累积相位、延迟时间、相互作用耦合强度和耦合点数目对量子Fisher信息演化的影响。结果表明当累积相位为特定值且耦合强度均匀时,量子Fisher信息演化能够增强并趋于一个稳定值。稳定的量子Fisher信息对应于免退相干相互作用,因而巨原子处于束缚态。研究有助于理解巨原子-波导系统的原子态量子Fisher信息增强。
Objective Quantum metrology leverages quantum effects to amplify estimation sensitivity and is applied to gravity wave detection, measurement standards, and super-resolution. As an important concept in quantum metrology and quantum estimation theory, quantum Fisher information(QFI) has attracted much attention from researchers. In quantum estimation theory, the QFI serves as a reliable quantity for evaluating the precision of parameter estimation. The Cramer-Rao theorem suggests that the lower bound of estimation precision is the inverse of the QFI. Consequently, quantum evolution that can increase the QFI is of paramount interest in quantum metrology. Recently, the non-Markovian dynamics induced by the giant-atom-waveguide system have captured considerable attention, and related advances have been made on quantum entanglement and quantum coherence. The effect of non-Markovianity induced by the giant-atom-waveguide system on QFI is a compelling subject that warrants examination. We aim to theoretically delineate the dynamics of the QFI for a giant-atom state coupling to a one-dimensional waveguide at multiple coupling points. A giant atom coupling to a onedimensional waveguide at multiple coupling points with different coupling strengths is considered and the dynamics of QFI encoded on the giant atom's state is analyzed. Specifically, the effect of the time delay, the different coupling strengths,and the number of coupling points on the QFI will be analyzed in detail. By a comparison between a small atom and a giant atom, we discern the quantum enhancement in the dynamics of a giant-atom-waveguide system. The analysis is expected to yield insights into the dynamics of QFI for a giant atom coupling to a one-dimensional waveguide.Methods We consider the model consisting of a giant atom coupling a one-dimensional waveguide at multiple coupling points and write out the Hamiltonian in position space. Utilizing Fourier transformation, we convert the Hamiltonian into momentum space. The time evolution of the quantum sta
作者
马小三
权家宏
路云宁
程木田
Ma Xiaosan;Quan Jiahong;Lu Yunning;Cheng Mutian(School of Electrical and Information Engineering,Anhui University of Technology,Ma'anshan 243032,Anhui,China)
出处
《光学学报》
EI
CAS
CSCD
北大核心
2024年第13期288-296,共9页
Acta Optica Sinica
基金
国家自然科学基金(11975023)
安徽省教育厅重大自然科学研究项目(2022AH040053)
安徽省教育厅高校自然科学研究重点项目(2023AH051078,2023AH051125)。
