A new diamond-based magnetic sensor uses a special “flaw” in diamonds that can be manipulated into sensitively monitoring magnetic signals from individual electrons and atomic nuclei placed nearby.

The system allows for nanoscale spatial resolution with nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) systems. It makes it possible to peer inside proteins, map the structure of impossibly intricate molecules, closely observe the dynamics of microscopic biochemical processes, monitor the activity of neural circuits, or use single electrons and nuclei for storing and processing information. Potentially, it may allow for imaging single nuclei in individual molecules.

Two important applications of this technique are a nanoscale magnetometer that could potentially detect precession of single nuclear spins and an optical magnetic-field imager combining spatial resolution ranging from micrometers to millimeters with a sensitivity approaching a few femtoTesla Hz^-1/2.

High-sensitivity diamond magnetometer with nanoscale resolution (abstract)