Kondo-assisted switching between three conduction states in capacitively coupled quantum dots

Abstract

We propose a nanoscale device consisting of a double quantum dot with strong intra- and interdot Coulomb repulsions. In this design, the current can only flow through the lower dot, but is triggered by the gate-controlled occupancy of the upper dot. At low temperatures, our calculations predict the double dot to pass through a narrow Kondo regime, resulting in highly sensitive switching characteristics between three well-defined states—insulating, normal conduction, and resonant conduction.