Experimental Observation of Kondo-Fano Resonant Tunneling in Silicon-Doped GaAs/AlAs Multiple Quantum Wells

TL;DR

This paper reports the experimental detection of Kondo-Fano resonant tunneling phenomena in silicon-doped GaAs/AlAs quantum wells, revealing temperature-dependent resonances and magnetic field splitting characteristic of Kondo physics.

Contribution

It provides the first experimental evidence of Kondo-Fano resonant tunneling in doped quantum wells, explained via an impurity Anderson model.

Findings

Observation of temperature-dependent Kondo resonance peaks.

Magnetic field splitting confirms Kondo resonance behavior.

Fano dips associated with Coulomb blockade of impurity states.

Abstract

We report experimental observation of Kondo-Fano resonant tunneling in Si-doped GaAs/AlAs multiple quantum wells. The spectrum of differential tunneling conductance at low bias shows a strong temperature dependent resonance, whose peak is split in the presence of a magnetic field, characteristic of a Kondo resonance. The data is well explained as a resonant tunneling of conduction electrons at the Fermi level through the doped silicon impurity states inside the wells by using an impurity Anderson model. The Coulomb blockade resonance of the impurity states induces a Fano dip above the Kondo resonance.