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Fitting magnetic field gradient with Heisenberg-scaling accuracy.

ABSTRACT: The linear function is possibly the simplest and the most used relation appearing in various areas of our world. A linear relation can be generally determined by the least square linear fitting (LSLF) method using several measured quantities depending on variables. This happens for such as detecting the gradient of a magnetic field. Here, we propose a quantum fitting scheme to estimate the magnetic field gradient with N-atom spins preparing in W state. Our scheme combines the quantum multi-parameter estimation and the least square linear fitting method to achieve the quantum Cramér-Rao bound (QCRB). We show that the estimated quantity achieves the Heisenberg-scaling accuracy. Our scheme of quantum metrology combined with data fitting provides a new method in fast high precision measurements.

SUBMITTER: Zhang YL

PROVIDER: S-EPMC4260217 | biostudies-literature | 2014 Dec

REPOSITORIES: biostudies-literature

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Fitting magnetic field gradient with Heisenberg-scaling accuracy.

Zhang Yong-Liang YL Wang Huan H Jing Li L Mu Liang-Zhu LZ Fan Heng H

Scientific reports 20141209

The linear function is possibly the simplest and the most used relation appearing in various areas of our world. A linear relation can be generally determined by the least square linear fitting (LSLF) method using several measured quantities depending on variables. This happens for such as detecting the gradient of a magnetic field. Here, we propose a quantum fitting scheme to estimate the magnetic field gradient with N-atom spins preparing in W state. Our scheme combines the quantum multi-param ...[more]

PMID: 25487218

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