Title
Enhancing parameter estimation precision by non-Hermitian operator process.
Abstract
Recently, Zhong et al. (Phys Rev A 87:022337, ) 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 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 , and in detail investigate the influence of operator parameters on the QFIs. Compared with pure decoherence process (without non-Hermitian operator process), we find that the operator process can potentially enhance and preserve the QFIs by choosing appropriate operator parameters, while with the help of the operator process one could completely 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.
Year
DOI
Venue
2017
https://doi.org/10.1007/s11128-017-1756-y
Quantum Information Processing
Keywords
Field
DocType
Parameter estimation,Non-Hermitian,Quantum Fisher information
Quantum mechanics,Operator (physics),Operator (computer programming),Quantum decoherence,Bloch sphere,Self-adjoint operator,Qubit,Amplitude,Hermitian matrix,Physics
Journal
Volume
Issue
ISSN
16
12
1570-0755
Citations 
PageRank 
References 
1
0.48
0
Authors
5
Name
Order
Citations
PageRank
You-Neng Guo133.37
maofa fang273.12
Guo-you Wang310.48
Jiang Hang422.61
Ke Zeng512.85