Magnetic induction imaging with a cold-atom radio frequency magnetometer

The sensitive detection of either static or radio frequency (RF) magnetic fields is essential to many fundamental studies and applications. Here, we demonstrate the operation of a cold-atom-based RF magnetometer in performing 1D and 2D imaging of small metallic objects. It is based on a cold 85Rb atomic sample and operates in an unshielded environment with no active field stabilization. It shows a sensitivity up to 200 pT / Hz in the 5 − 35 kHz bandwidth range and can resolve a 0.4 mm wide cut in a 0.8 mm thick metallic foil. The characteristics of our system make it a good candidate for applications in civil and industrial surveillance.