当前位置: X-MOL 学术Int. J. Quantum Inf. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Quantum frequency estimation with conditional states of continuously monitored independent dephasing channels
International Journal of Quantum Information ( IF 0.7 ) Pub Date : 2020-02-07 , DOI: 10.1142/s0219749919410132
Francesco Albarelli 1 , Matteo A. C. Rossi 2 , Marco G. Genoni 3
Affiliation  

We discuss the problem of estimating a frequency via [Formula: see text]-qubit probes undergoing independent dephasing channels that can be continuously monitored via homodyne or photo-detection. We derive the corresponding analytical solutions for the conditional states, for generic initial states and for arbitrary efficiency of the continuous monitoring. For the detection strategies considered, we show that: (i) in the case of perfect continuous detection, the quantum Fisher information (QFI) of the conditional states is equal to the one obtained in the noiseless dynamics; (ii) for smaller detection efficiencies, the QFI of the conditional state is equal to the QFI of a state undergoing the (unconditional) dephasing dynamics, but with an effectively reduced noise parameter.

中文翻译:

具有连续监测的独立相移通道条件状态的量子频率估计

我们讨论了通过[公式:见文本]-qubit 探针估计频率的问题,这些探针经历独立的相移通道,可以通过零差或光电检测连续监测。我们为条件状态、通用初始状态和连续监测的任意效率推导出相应的解析解。对于所考虑的检测策略,我们表明:(i)在完美连续检测的情况下,条件状态的量子Fisher信息(QFI)等于在无噪声动力学中获得的信息;(ii) 对于较小的检测效率,条件状态的 QFI 等于经历(无条件)移相动态的状态的 QFI,但噪声参数有效降低。
更新日期:2020-02-07
down
wechat
bug