零差检测量子反馈下的相位估计  

Phase Estimation under Homodyne-Mediated Quantum Feedback

作　　者：胡要花[1] 陶亚萍[1] HU Yao-hua;TAO Ya-ping(Physics and Electronic Information College,Luoyang Normal College,Luoyang 471934,China)

机构地区：[1]洛阳师范学院物理与电子信息学院,河南洛阳471934

出　　处：《量子光学学报》2020年第3期258-263,共6页Journal of Quantum Optics

基　　金：国家自然科学基金(U1204616,11804141);河南省高校青年骨干教师培养计划(2018GGJS129);河南省高等学校重点科研项目计划(16A140013)资助的课题.

摘　　要：考虑零差检测量子反馈下的单模腔场与二能级原子相互作用系统,研究反馈控制和初始状态对量子相位参数估计的影响.结果表明:无反馈时,量子费希尔信息随时间很快衰减.然而,在初始参数θ和φ均取(π/2)时,反馈参数λ=±0.5左右量子费希尔信息达到最大值,该结果表明只要参数选择合适,零差检测量子反馈可以使得量子费希尔信息的衰减有效延缓,二能级原子相位估计精度的上限提高.此外原子初始状态的权重参数和相对相位对量子费希尔信息的演化也有很大影响.This paper considers a two-level atom interacting with a single-mode cavity under homodyne-mediated quantum feedback and studies the effect of the feedback control and the initial condition of the system on the estimation of the phase parameter.The results show that the quantum Fisher information attenuates to zero quickly with time in the absence of quantum feedback.However,when the homodyne-mediated feedback is performed,the decay of the quantum Fisher information can be delayed as long as the values of the feedback and initial parameters are suitable,and the upper limit of the estimation precision of the phase estimation can be improved.In addition,the initial values of the weight parameter and the relative phase of the atom have a great influence on the quantum Fisher information.

关 键 词：量子费希尔信息 零差检测量子反馈 二能级原子 相位估计 

分 类 号：O431[机械工程—光学工程]