Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Proper temperature for Cs atomic magnetometer

Qiang Liu, Junhai Zhang, Xianjin Zeng, Jiuxing Li, Qingmeng Li, Qiang Huang, Simiao Han, Zongjun Huang, Weimin Sun

Published Nov 18, 2011• 0 citations

Abstract

Alkali atomic magnetometer is a good choice for magnetic testing devices with very-high sensitivity. Many parameters could affect the sensitivity of the atomic magnetometer. In this paper we described a Cs atomic magnetometer operating at normal temperature. A circularly polarized pumping light is used to polarize Cs atoms, while a linear polarized probing light is used to test the magneto-caused polarization rotation. During the experiment, we found the temperature is a very important parameter for the signal-to-noise ratio(SNR) enhancement. On the one hand, the higher temperature makes the SNR higher, which is good for sensitivity. On the other hand, the higher temperature causes more frequent collisions between the Cs atoms and the Cs atom and container wall, so that the polarization is easy to be broken, which reduces its sensitivity. So there must be a proper temperature for the high-sensitivity atomic magnetometer. We measured the magnetometer linewidth and sensitivity in the experiment. At optimum temperature the magnetometer achieves magnetic field sensitivity of 3.2pT/Hz1/2.

DOI: 10.1117/12.907133

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