Scanning probes are revolutionizing the study of materials atomic and mesoscopic length scales. We are moving beyond point measurements to develop a cryogenic scanning tunneling potentiometer capable of investigating transport process in superconductors, grain boundaries and domain walls, and inhomogenrious materials, all on submicron length scales.
Reference: Potentiometric imaging of (La-Sr)MnO3 thin films, J.J. Versluijs, F. Ott, and J.M.D. Coey, App. Phys. Lett. 75, 1152 (1999).