High Kondo temperature (TK ~ 80 K) in self-assembled InAs quantum dots laterally coupled to nanogap electrodes

TL;DR

This study demonstrates a high Kondo temperature of approximately 81 K in self-assembled InAs quantum dots coupled to nanogap electrodes, marking a significant advancement in quantum nanostructure research.

Contribution

The paper reports the first observation of an exceptionally high Kondo temperature in self-assembled InAs quantum dots with strong electrode coupling.

Findings

Kondo temperature TK ~ 81 K observed

Clear Coulomb blockade effects demonstrated

Strong coupling achieved in quantum dot-electrode system

Abstract

We have fabricated single electron tunneling structures by forming nanogap metallic electrodes directly upon single self-assembled InAs quantum dots (QDs). The fabricated samples exhibited clear Coulomb blockade effects. Furthermore, a clear Kondo effect was observed when strong coupling between the electrodes and the QDs was realized using a large QD with a diameter of ~ 100 nm. From the temperature dependence of the linear conductance at the Kondo valley, the Kondo temperature TK was determined to be ~ 81 K. This is the highest TK ever reported for artificial quantum nanostructures.