Fano versus Kondo Resonances in a Multilevel "Semi-Open" Quantum Dot

TL;DR

This paper investigates the interplay of Fano and Kondo resonances in a large semi-open quantum dot, revealing how Kondo correlations suppress Fano interference effects in conductance measurements.

Contribution

It provides a detailed analysis of how Kondo correlations influence Fano resonances in a multilevel quantum dot, aligning theoretical results with experimental observations.

Findings

Kondo correlations damp Fano oscillations in conductance.

Antiresonances are washed out at low temperatures.

Results agree with experimental data for semi-open quantum dots.

Abstract

Linear conductance across a large quantum dot via a single level e_0 with large hybridization to the contacts is strongly sensitive to quasi-bound states localized in the dot and weakly coupled to e_0. It oscillates with the gate voltage due to interference of the Fano type. At low temperature and Coulomb blockade, Kondo correlations damp the oscillations on an extended range of gate voltage values, by freezing the occupancy of the e_0 level itself. As a consequence, antiresonances of Fano origin are washed out. The results are in good correspondence with experimental data for a large quantum dot in the semi-open regime.