A new class of electroninteractions in quantum systems

Physicists at the University of new South Wales have observed a new kind of interaction that can arise between electrons in a single-atom silicon transistor. The findings, to be published this week in the journal Physical
Review Letters, offer a more complete understanding of the
mechanisms for electron transport in nanostructures at the atomic level. "We have been able to study some of the most complicated transport mechanisms that can arise up to the single atom level," says lead author Dr giuseppe C. tettamanzi, from the School of Physics at UNSW. The results contained in this study open the door for new quantum electronic schemes inwhich it is the orbital nature of the electrons – and not their spin or their charge – that plays a major role, he says. The study, in collaboration with scientists from the ICMM in madrid and the Kavli Institute in the netherlands, describes how a single electron bound to a dopant atom in a silicon matrix can interact with many electrons throughout the transistor. In these geometries, electron-electron interactions can be dominated by something called the Kondo effect.conventionally, this arises from the spin degree of freedom,which represents an angular momentum intrinsic to each electron and is always in the up or in the down state.
www.eurekalert.org/pub_releases/2012-01/uons-anc012212.php

 

I felt obliged to post the rest of the article. I'm not sure what they mean by symetry cross-over, but I think I get the general idea.

Violating Ohm's Law is a pretty big deal all by itself.