Physical Review Applied

Enhancement of the Signal-to-Noise Ratio of an Atomic Magnetometer by 10 dB

Guzhi Bao, Shuhe Wu, Shuqi Liu, Wenfeng Huang, Ziran Li, L. Q. Chen, Chun-Hua Yuan, Weiping Zhang

Published May 28, 2019• 9 citations

Abstract

Nonlinear magneto-optical rotation (NMOR) is a sensitive technique for measuring magnetic fields, though the polarization self-rotation (PSR) effect is a fundamental source of excess quantum noise that limits its sensitivity. This study uses a phase shifter to solve the limitation due to the PSR effect. Implementation of the phase shifter improves the signal-to-noise ratio up to 10 dB in the range of Earth's magnetic field. This approach should be useful for high-sensitivity magnetic field measurements in a geomagnetic environment.

DOI: 10.1103/physrevapplied.11.054075

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