Fig. 1: Working principle and schematics of the single-shot all optical vector magnetometer.

a Frequency modulated elliptically polarized light interacts with the 87Rb atom, coupling the ground state 5 2S1/2(F = 2) and the excited state 5 \({}^{2}{{{{{{{{\rm{P}}}}}}}}}_{1/2}\,({F}^{{\prime} }=1)\). With the direction of the total magnetic field set as the quantization axis, atomic levels exhibit Zeeman splitting. Frequency modulation of the laser gives rise to frequency sidebands with the intervals of the modulation frequency ωm near the Larmor frequency ΩL. The σ+, σ−, π components of the laser form multiple sets of EIT. b Schematics of the experiment setup. ECDL external cavity diode laser, HWP half-wave plate, QWP quarter-wave plate, PBS polarization beam splitter, PC personal computer.