Quantum metrology with a non-Markovian qubit system

• 来源期刊: 中国物理B（英文版）
• 关键词: quantum metrology quantum Fisher information time-convolutionless parameter estimation
• 年，卷（期）: 2018,（12）
• 页码范围: 196-201
• 页数: 6页
• 语种: 英文
• DOI: 10.1088/1674-1056/27/12/120301

摘要

The dynamics of the quantum Fisher information (QFI) of phase parameter estimation in a non-Markovian dissipative qubit system is investigated within the structure of single and double Lorentzian spectra. We use the time-convolutionless method with fourth-order perturbation expansion to obtain the general forms of QFI for the qubit system in terms of a non-Markovian master equation. We find that the phase parameter estimation can be enhanced in our model within both single and double Lorentzian spectra. What is more, the detuning and spectral width are two significant factors affecting the enhancement of parameter-estimation precision.