Fig. 1. Schematic diagram of Larmor precession

Fig. 2. Internal composition diagrams of optically pumped magnetometers (QWP: quarter wave plate; HWP: half wave plate; PBS: polarization beam splitter). (a) Schematic diagram of a single-beam optically pumped magnetometer; (b) schematic diagram of a two-beam optically pumped magnetometer

Fig. 3. Schematic diagrams of optically pumped magnetometer principle. (a) Schematic diagram of the operation of an optically pumped magnetometer^[40]; (b) ⁸⁷Rb atomic level diagram

Fig. 4. Schematic diagrams of optical pumping principle. (a) Optical pumping principle without buffered and quenched gases; (b) optical pumping principle with buffered and quenched gases

Fig. 5. Schematic diagrams of experimental setup for different magnetometers. (a) Optically pumped magnetometer with elliptically polarized light pumping^[48]; (b) elliptically polarized light pumped rubidium atomic magnetometer^[50]; (c) schematic diagram of a two-beam optically pumped magnetometer based on polarization modulation technology^[55]; (d) single-beam SERF magnetometer with elliptical polarization modulated by magnetic field^[56]

Fig. 6. Light fields and their polarization state distributions^[57]. (a) Scalar light field and its polarization state distribution; (b) vector light field and its polarization state distribution

Fig. 7. Research on vector light in magnetic field measurement. (a) Schematic diagram of the experimental device for magnetic field measurement based on CVB to achieve synchronous detection of magnetic field strength and direction^[13]; (b) theoretical simulation results of synchronous detection of magnetic field strength and direction based on CVB^[13]; (c) schematic diagram of a radial polarization vector light measurement magnetic field experimental device based on magnetic nanoparticle suspension^[15]; (d) schematic diagram of vector light measurement experimental device for alternating magnetic field^[16]

Fig. 8. Working mechanism of dichroism. (a) Atomic wire dichroism^[85]; (b) atomic circle dichroism^[85]; (c) vector light detection of atomic circular dichroism^[86]

Fig. 9. Magnetic field induced birefringence experiment. (a) Four level structure of atomic transitions in the optical rotation effect^[91]; (b) magnetic field induced circular birefringence experimental setup and Zeeman level shift^[60]; (c) nonlinear Faraday rotation experimental setup in cold atoms^[94]

Fig. 10. Magnetic field measurement using vector light. (a) Experimental optical path diagram of vector light in atomic ensemble and comparison of data results between FGR and Bloch models after Fourier transform^[62]; (b) relationship between interference patterns and polarization rotation angle changes under different magnetic fields^[60]; (c) lateral polarization and intensity distribution results of vector beam after passing through the air chamber^[95]

Fig. 11. Vector light solves the “dead zone” problem in a single-beam pump magnetometer. (a) Experimental schematic diagram of a vector polarized light driven magneto-optical resonance single-beam magnetometer^[97]; (b) dependence of MOR signal absorption linear fitting and transmission signal amplitude angle^[97]; (c) a dead zone free single-beam atomic magnetometer based on mixed Poincaré beams^[105]