Nanoscale magnetic field mapping with a single spin scanning probe magnetometer
We demonstrate quantitative magnetic field mapping with nanoscale resolution, by applying a lock in technique on the electron spin resonance frequency of a single nitrogen vacancy defect placed at the apex of an atomic force microscope tip. In addition, we report an all optical magnetic imaging technique which is sensitive to large off axis magnetic fields, thus extending the operation range of diamond based magnetometry. Both techniques are illustrated by using a magnetic hard disk as a test sample. Owing to the non perturbing and quantitative nature of the magnetic probe, this work should open up numerous perspectives in nanomagnetism and spintronics.