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

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 $∼100nm$⁠. From the temperature dependence of the linear conductance at the Kondo valley, the Kondo temperature $TK$ was determined to be $∼81K$⁠. This is the highest $TK$ ever reported for artificial quantum nanostructures.