Harbin Gongcheng Daxue Xuebao/Journal of Harbin Engineering University

Effect of the geomagnetic field on the resonance spectral lines of the Cs magnetometer

LI Qingmen

Published Jan 1, 2013• 0 citations

Abstract

In order to study the effect of the geomagnetic field on cesium magnetometer sensitivity,the Breit-Rabi equation is used to analyze the Zeeman splitting of the F g = 4 level of Cs atoms. The emphasis is on the analysis of the nonlinear Zeeman effect on the resonant hyperfine spectrum of the all-optical atomic magnetometer in the geomagnetic field which is about 0.05 mT. The results show that the effect would cause the line-width to increase from 20 Hz to 53 Hz,and the amplitude to decrease by relatively 50%. If any accessional noise is not taken into account,our cesium magnetometer sensitivity will deteriorate from 0.3 pT / Hz1 /2to 1.6 pT / Hz1 /2. That showed a technical bottleneck of improving atomic magnetometer sensitivity in the geomagnetic field. A new technique of pumping from F g = 4 to F e = 4 is proposed to break through this bottleneck.

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