Fano effect of a strongly interacting quantum dot in contact with superconductor

TL;DR

This paper investigates the interplay of the Fano effect and Kondo physics in a quantum dot within an Aharonov-Bohm interferometer connected to normal and superconducting leads, revealing conductance suppression due to Fano dominance.

Contribution

It provides a theoretical analysis of how Fano and Kondo effects influence transport in a quantum dot system with superconducting contacts, extending understanding of quantum interference phenomena.

Findings

Conductance is suppressed as the Fano effect becomes more dominant.

The theory applies to both N-AB-S and S-AB-S junctions.

Highlights the interplay between Kondo physics and Fano interference.

Abstract

The physics of a system consisting of an Aharonov Bohm (AB) interferometer containing a single level interacting quantum dot (QD) on one of its arms, and attached to normal (N) and superconducting (S) leads is studied and elucidated. Here the focus is directed mainly on N-AB-S junctions but the theory is capable of studying S-AB-S junctions as well. The interesting physics comes into play under the conditions that both the Kondo effect in the QD and the the Fano effect are equally important.It is found the conductance of the junction is suppressed as the Fano effect becomes more dominant.