Millimeter-Resolution Scanning Miniaturized Magnetometer Based On Diamond Quantum Sensor

We have developed a miniaturized magnetic sensor based on diamond nitrogen-vacancy (NV) centers, combined with a two-dimensional scanning setup that enables imaging of magnetic samples with millimeter-scale resolution. Using the lock-in detection scheme, we tracked changes in the NV’s spin resonances induced by the magnetic field from target samples. By scanning over a toy diorama with hidden magnets, we simulate scenarios such as remote detection of landmines on a battlefield or locating concealed objects at a construction site. The obtained magnetic images reveal that they can be influenced and distorted by the choice of frequency point used in the lock-in detection, as well as the magnitude of the sample’s magnetic field. Through magnetic simulations, we find good agreement between the measured and simulated images. This work introduces a novel imaging method using a scanning miniaturized magnetometer to detect hidden magnetic objects, with potential applications in military and industrial sectors.