文献类型：期刊文献

英文题名：Enhancing parameter estimation precision by non-Hermitian operator process

作者：Guo, You-neng[1,2,3];Fang, Mao-fa[2,3];Wang, Guo-you[4];Hang, Jiang[5];Zeng, Ke[1]

机构：[1]Changsha Univ, Dept Elect & Commun Engn, Changsha 410022, Hunan, Peoples R China;[2]Hunan Normal Univ, Minist Educ, Key Lab Low Dimens Quantum Struct & Quantum Contr, Changsha 410081, Hunan, Peoples R China;[3]Hunan Normal Univ, Dept Phys, Changsha 410081, Hunan, Peoples R China;[4]Hunan Univ Technol, Coll Sci, Zhuzhou 412008, Peoples R China;[5]Guangdong Ocean Univ, Phys & Photoelect Sci Dept, Zhanjiang 524088, Peoples R China

年份：2017

卷号：16

期号：12

外文期刊名：QUANTUM INFORMATION PROCESSING

收录：SCI-EXPANDED(收录号：WOS:000414496700001)、、EI(收录号：20174504373891)、Scopus(收录号：2-s2.0-85032820778)、WOS

基金：This research is supported by the Funds of the National Natural Science Foundation of China under (Grant No. 11374096), the Natural Science Foundation of Hunan Province (Grant Nos. 2017JJ3346 and 2016JJ2045), the Start-up Funds for Talent Introduction and Scientific Research of Changsha University 2015 (SF1504), Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education (QSQC1403) and Scientific Research Project of Hunan Province Department of Education (16C0134 and 16C0469)

语种：英文

外文关键词：Parameter estimation; Non-Hermitian; Quantum Fisher information

外文摘要：Recently, Zhong et al. (Phys Rev A 87: 022337, 2013) investigated the dynamics of quantum Fisher information (QFI) in the presence of decoherence. We here reform their results and propose two schemes to enhance and preserve the QFIs for a qubit system subjected to a decoherence noisy environment by applying non-Hermitian operator process either before or after the amplitude damping noise. Resorting to the Bloch sphere representation, we derive the exact analytical expressions of the QFIs with respect to the amplitude parameter. and the phase parameter phi, and in detail investigate the influence of non-Hermitian operator parameters on the QFIs. Compared with pure decoherence process (without non-Hermitian operator process), we find that the postnon-Hermitian operator process can potentially enhance and preserve the QFIs by choosing appropriate non-Hermitian operator parameters, while with the help of the priornon-Hermitian operator process one could xcompletely eliminate the effect of decoherence to improve the parameters estimation. Finally, a generalized non-Hermitian operator parameters effect on the parameters estimation is also discussed.