Experimental evidence for spinless Kondo effect in two electrostatically coupled quantum dot systems

The Kondo effect was originally observed in metals doped with magnetic impurities. Recent experiments demonstrated Kondo resonances in the electrical transport through quantum dot systems. They were predicted from the Anderson impurity model by replacing the magnetic impurity by a spin-degenerate state in the quantum dot. Studies of the Kondo effect in such quantum dot systems benefit from enhanced tunability of the relevant parameters present in the Anderson impurity model. Here we demonstrate an experimental realization of the Anderson model showing a spinless Kondo resonance due to an electrostatic degeneracy: two electrostatically coupled quantum dots with separate leads.