1ST IMAGES FROM A MAGNETIC-RESONANCE FORCE MICROSCOPE

We describe a new magnetic resonance imaging technique based on the me asurement of magnetic force acting between a magnetic tip and the reso nantly excited spins in the sample. Magnetic resonance force maps of t he sample are formed by scanning the tip with respect to the sample wh ile measuring the angstrom-scale vibration of a microcantilever holdin g the sample. Real-space spin density information can be recovered fro m the force maps by using a simple image reconstruction technique. The technique was demonstrated for electron spin resonance m micrometer-s ize particles of diphenylpicrylhydrazil. Using a tip that generates a field gradient of 4.3 G/mum, a lateral resolution of 5 mum, and an axi al resolution of 1 mum was achieved.