VCSEL frequency stabilization for optically pumped magnetometers

Optically pumped magnetometers (OPMs) have developed rapidly in the bio-magnetic measurement field, which requires lasers with stable frequency and intensity for high sensitivity. Herein we stabilize a vertical-cavity surface-emitting laser (VCSEL) without any additional setup except parts of an OPM. The linewidth absorption spectrum as reference is broadened to 40 GHz owing pressure broadening. To enhance performance, VCSEL injection current temperature are tuned simultaneously using closed-loop control system. experiments reveal that stability achieves 2×10-7 at average time 1 s, noise 1×10-6 V/Hz1/2 1–100 Hz. This approach useful suppressing OPM sensor probe parts.