Robust, high-speed, all-optical atomic magnetometer
A self-oscillating magnetometer based on the nonlinear magneto-optical rotation effect with separate modulated pump and unmodulated probe beams is demonstrated. This device possesses a bandwidth exceeding 1 kHz. Pump and probe are delivered by optical fiber, facilitating miniaturization and modularization. The magnetometer has been operated both with vertical-cavity surface-emitting lasers, which are well suited to portable applications, and with conventional edge-emitting diode lasers. A sensitivity of around 3 nG is achieved for a measurement time of 1 s.