The Kondo effect in surface physics and in quantum dots

Full text: The Kondo effect involves the interaction of a localized magnetic impurity with the conduction electrons of a metal. Thermodynamic and transport properties have been thoroughly studied for many years and it is one of the few examples of a strongly correlated electron system for which we have a good theoretical understanding. However, recent measurements of the conductance through quantum dot devices have shown clear evidence for the presence of the Kondo effect, demonstrating that its existence is not restricted only to magnetic impurities in metals. Another possible area where the Kondo effect may be observable is in atom-surface scattering. We introduce a theoretical approach based on a systematic expansion of the system's wavefunction in particle-hole pairs to show that the Kondo screening cloud may reveal itself in the scattering of alkaline-earth atoms off metal surfaces, through an anomalous increase in the neutralization probabilities as the temperature is lowered. The temperature dependence of the conductance through quantum dot devices will also be analyzed by means of the same approach