The Kondo Effect in Quantum Dots(<Special Issue>Rejuvenation of the Kondo Effect : 40 Years Old)

Abstract

The Kondo effect in quantum dots arises from singlet coupling of a spin half electron localized in a quantum dot to Fermi electrons in the contact leads. This quantum dot then plays a role of a magnetic impurity. In addition, for quantum dots various important parameters associated with the Kondo effect such as spin configuration, state degeneracy and the way of coupling to contact leads are all tunable, and this enables novel approaches for the Kondo physics. In this article we describe such examples, which are observations of the unitary limit Kondo effect and enhancement of the Kondo effect by state degeneracy.