Single-Beam Double-Pass Miniaturized Atomic Magnetometer for Biomagnetic Imaging Systems

Miniaturized atomic magnetometers (AMs), particularly spin-exchange relaxation-free (SERF) AMs, have been emerging in clinical imaging applications such as magnetocardiography (MCG) and magnetoencephalography (MEG). Miniaturization, portability, low cost are primary development targets for biomagnetic technologies, well high sensitivity, temporal, spatial resolution. In this article, we propose a low-cost solution system based on which one laser source is used multichannel AM sensor array. A novel design demonstrated miniaturized SERF AM, consisting of single-beam double-pass configuration an optical fiber circulator. The effects temperature power the zero-field magnetic resonance linewidth characterized, experimental results show that present achieves better performance, compared with traditional single-pass configuration. field noise spectrum shows AMs reach sensitivity approximately 86 fT/Hz $^{{1}/{2}}$ at frequency 10 Hz when operating single-channel mode 40 differential two sensors sharing 6-mm baseline. typical adult MCG signal all visible P, QRS-complex, T waves recorded by magnetometer mode. This especially suitable arrays basic building element systems.