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Estimation of fluctuating magnetic fields by an atomic magnetometer

Vivi Petersen·Klaus Molmer
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Abstract

We present a theoretical analysis of the ability of atomic magnetometers to estimate a fluctuating magnetic field. Our analysis makes use of a Gaussian state description of the atoms and the probing field, and it presents the estimator of the field and a measure of its uncertainty which coincides in the appropriate limit with the achievements for a static field. We show by simulations that the estimator for the current value of the field systematically lags behind the actual value of the field, and we suggest a more complete theory, where measurement results at any time are used to update and improve both the estimate of the current value and the estimate of past values of the B-field.

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Vivi Petersen, Klaus Molmer. 2006-05-29. Estimation of fluctuating magnetic fields by an atomic magnetometer. https://doi.org/10.1103/physreva.74.043802

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