A novel Kondo effect in single atom transistors

We report the first observation of the Kondo effect in a single gate-tunable atom transistor fabricated using a complementary-metal-oxide-semiconductor (CMOS) compatible architecture. In this new geometry the presence of both orbital and of spin degrees of freedom leads to a considerably higher Kondo temperature and allows for tunability of the effect. The described mechanisms of transport are of fundamental importance for silicon nano-electronics as they demonstrate once again the influence of the valleys in determining the electronic properties of Si nano-structures.