Design of low-noise, fast-response electronics for high-performance helium optically pumped magnetometers

High-sensitivity and wide-bandwidth magnetometers are crucial for both terrestrial and space-based geophysical applications. In this work, we present an electronics design tailored for a helium optically pumped magnetometer (He-OPM) operating under ambient geomagnetic field conditions. The proposed design features low noise and fast response, which are critical for achieving high bandwidth and high sensitivity in He-OPMs. In addition, a phase compensation method is introduced to reduce phase errors introduced by the signal transmission path, including electronic delays, thereby improving measurement accuracy. The system performance is evaluated in a laboratory environment using a frequency-stabilized laser and effective magnetic shielding. Experimental results demonstrate that the influence of the electronics on measurement accuracy is below 40 pT per 1 μT, and the system achieves a bandwidth of 650 Hz. Under an applied magnetic field of ∼0.65 μT, the He-OPM achieves a sensitivity of 620fT/Hz@1Hz in closed-loop operation.