Crossing of two Coulomb-Blockade Resonances

TL;DR

This paper provides a theoretical analysis of electron transport through an Aharonov-Bohm interferometer with two quantum dots, focusing on how Coulomb-blockade resonances interact and cross, affecting conductance.

Contribution

It introduces explicit scattering matrix expressions for coupled quantum dot resonances in an AB interferometer, emphasizing the resonance crossing phenomena.

Findings

Resonance crossing significantly influences transport properties.

Explicit formulas relate scattering matrix to resonance energies and AB phase.

Theoretical framework applicable to non-interacting electron transport in quantum dot systems.

Abstract

We investigate theoretically the transport of non--interacting electrons through an Aharanov--Bohm (AB) interferometer with two quantum dots (QD) embedded into its arms. In the Coulomb-blockade regime, transport through each QD proceeds via a single resonance. The resonances are coupled through the arms of the AB device but may also be coupled directly. In the framework of the Landauer--Buttiker approach, we present expressions for the scattering matrix which depend explicitly on the energies of the two resonances and on the AB phase. We pay particular attention to the crossing of the two resonances.