Multi-channel Magnetic Microscope with an Optically Pumped Magnetometer and Flux Guides

High-resolution, high-sensitivity magnetic field imaging technology is crucial in biomedical and materials science; however, enhancing spatial resolution often reduces sensitivity due to a trade-off between them and thus current technology struggles to image low field, small-scale systems like neural networks, limited to acquiring signals from 10⁴ to 10⁵ neurons. Additionally, magnetic fields from areas of interest must be mapped simultaneously within reasonable acquisition times for imaging live subjects or biological matter, which poses additional challenges in advancing a magnetic imaging system. To address these demands, we develop a high-resolution, high-sensitivity magnetic microscope that integrates a multi-channel optically pumped magnetometer (OPM) with an array of high-permeability flux guides (FGs). The multi-channel FG-OPM device enables simultaneous magnetic field imaging of multiple sources with unprecedented combination of spatial resolution and sensitivity. We anticipate that this device has many potential applications, such as imaging small-scale neural networks and magnetic nano-particles. Here, we present our recent experimental and numerical studies on implementing the device.