Scanning tunneling potentiometry

In certain problems of electrical transport through condensed matter, it is important to know the potential distribution with microscopic resolution, e.g., at interfaces (Schottky barriers) or pn junctions. Scanning tunneling potentiometry, a new application of scanning tunneling microscopy, is capable of providing this information. The tunnel current is used for simultaneously sensing probe-to-sample distance and local potential. The method was tested with a gold-island metal-insulator-metal structure.