Transverse relaxation determination based on light polarization modulation for spin-exchange relaxation free atomic magnetometer

Abstract

A transverse relaxation determination of spin-exchange relaxation free (SERF) magnetometer based on polarization modulation technique is proposed. Compared with the radio-frequency (RF) excitation and light intensity excitation methods used in SERF magnetometer, the light polarization modulation method has a high stability in low-frequency range, which indicates a more accurate transverse relaxation measurement.

Transient electromagnetically induced transparency spectroscopy of 87Rb atoms in buffer gas

“…The determined time is of several tens of µs for 87 Rb, which is in the same order of the intrinsic relaxation time of Cs for a magnetometer. [31,32] Many factors can account for the small values. In our case, the relaxation occurs under the illumination of the probe beam in the whole evolution process, which accelerates the depolarization of the ground state by dumping transition from the upper Zeeman sub-states.…”

Theoretical study of the close-loop atomic magnetometer with a transverse pumping feedback

“…Furthermore, the inductance of the compensation coil also limits the bandwidth of the feedback system. The second one (method 2 in figure 2) adjusts the polarization of laser to compensate the polarization rotation caused by the atoms in the vapor cell, such as the Faraday rotator [12,13], liquid crystal variable retarder [14], photo elastic modulator [15], et al However, the feedback cannot increase the measurement range limited by the SERF linewidth and the variation of k 2 cannot be eliminated. Comparatively, the feedback scheme (show in figure 2) proposed in this work can eliminate both the variation of k 2 and k 3 , and no three-dimensional coils are needed.…”