Tenth International Conference on Information Optics and Photonics

Suppression of mechanical error in micro-rotation-angle measurement of optical pumped atomic magnetometers

Huiyu Li, Kaibin Cui, Yu Wang, Guangwei Chen

Published Nov 24, 2023• 0 citations

Abstract

The measurement of ultra-weak magnetic fields relies on the conversion of magnetic field information to atom spins using alkali metals. In this context, the detection of magnetic fields is accomplished through rotation angle measurement of linearly polarized light. This paper proposes a novel method to suppress mechanical errors between polarizers in the rotation angle measurement, taking advantage of the optical setup characteristics in atomic magnetometers. The method involves applying two separate frequency modulations to the pump beam and probe beam, effectively eliminating mechanical errors between the polarizers as a direct current component using a double-channel lock-in amplifier. Additionally, the double modulation method offers a solution to suppress shot noise caused by incident beam fluctuations or transverse spin relaxation, as well as mechanical errors among optical elements in the light path, enabling high-precision measurements.

DOI: 10.1117/12.3005437

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