From IEEE Spectrum:http://spectrum.ieee.org/semiconductors/nanotechnology/ohms-law-survives-at-the-atomic-scale
Image: Bent Weber
Atomic Bridge: The template for a 1.5-nanometer-wide nanowire
was made by pushing atoms around using a scanning tunneling microscope.
The resulting nanowire showed that Ohm's Law works even for wires just 4
atoms thick. Click on image to enlarge.
Saswato R. Das, a New York City–based writer, contributes frequently to IEEE Spectrum. In September 2011 he reported on advances that could bring us closer to practical quantum computing.