Suppression of the magnetic noise response caused by elliptically polarized light in an optical rotation detection system

We analyze and suppress the magnetic noise response in optical rotation detection system (ORDS) in atomic magnetometers in this study. Because of the imperfections of the optical elements, the probe light is actually elliptically polarized in ORDS, which can polarize the atom ensemble and cause the responses to the three-axis magnetic noise. We theoretically analyze the frequency responses to the magnetic noise, and prove that the responses are closely associated with the DC magnetic field. The values of the DC magnetic fields are calculated with special frequency points, called 'break points', in the transverse responses. We reveal the relationships between the DC magnetic field and the sensitivities of ORDS, and effectively suppress the magnetic noise responses with the residual magnetic field compensation. Finally, the sensitivity of ORDS is improved by approximately two times at 10-20 Hz. (C) 2022 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement

Automated summary

This study focuses on analyzing and suppressing the magnetic noise response in the optical rotation detection system (ORDS) of atomic magnetometers. The research reveals the close relationship between the responses to magnetic noise and the DC magnetic field. By calculating the values of the DC magnetic fields using specific frequency points, referred to as "break points," it is possible to effectively suppress the magnetic noise responses. Through residual magnetic field compensation, the sensitivity of the ORDS is significantly improved, approximately two times higher at a frequency range of 10-20 Hz.