Transmission Phase Shift of a Quantum Dot with Kondo Correlations

TL;DR

This paper investigates how Kondo correlations influence the transmission phase shift in a quantum dot system, predicting observable effects on phase behavior related to voltage, gate voltage, and temperature, enabling direct measurement of the scattering phase shift.

Contribution

It provides detailed predictions on the impact of Kondo resonance on phase shifts, facilitating the first direct observation of the pi/2 scattering phase shift in such systems.

Findings

Kondo correlations significantly alter the transmission phase shift.

Development of a Kondo resonance affects phase dependence on experimental parameters.

First direct measurement of the pi/2 scattering phase shift is proposed.

Abstract

We study the effects of Kondo correlations on the transmission phase shift of a quantum dot in an Aharonov-Bohm ring. We predict in detail how the development of a Kondo resonance should affect the dependence of the phase shift on transport voltage, gate voltage and temperature. This system should allow the first direct observation of the well-known scattering phase shift of pi/2 expected (but not directly measurable in bulk systems) at zero temperature for an electron scattering off a spin-1/2 impurity that is screened into a singlet.