Reflection-Compensated Orthogonal Non-Overlapping Uniform Pumping Scheme For Triaxial Serf Atomic Magnetometers

Triaxial spin-exchange relaxation-free (SERF) atomic magnetometer has attracted widespread attention for its capability of measuring the total magnetic field vector information. In this paper, we propose a triaxial SERF atomic magnetometer through orthogonal non-overlapping pumping beam with improved atom spin polarization spatial uniformity by using a uniformized pump beam and reflection compensation. The homogenized beams are adopted to achieve uniform transverse polarization, while double-pass reflection compensation is integrated to realize uniform longitudinal polarization. The polarizability distribution based on an effective optical path-length formalism was obtained via theoretical simulation. The bandwidth, dispersion curves, stability, and sensitivity were experimentally analyzed under three configurations: uniformized pump beam, gaussian pump beam-reflection compensation, and uniformized pump beam-reflection compensation. Results of experiments reveal that the proposed configuration enhances three-axis bandwidth by roughly 10 (Formula presented.) and improves X, Y, and Z sensitivities by approximately 35 (Formula presented.), 60 (Formula presented.), and 30 (Formula presented.), respectively, achieving sensitivities of 20.56 fT/ (Formula presented.) (X), 30.75 fT/ (Formula presented.) (Y) and 20.54 fT/ (Formula presented.) (Z) at 140 (Formula presented.) and 2 mW. These results demonstrate a structurally simple yet highly effective approach for achieving high uniformity and stability in three-axis vector magnetic sensing, with strong potential for applications such as spatial magnetic-field mapping and bio-magnetic measurement research.