Interplay of Coulomb interaction and spin-orbit effects in multi-level quantum dots

TL;DR

This paper investigates how Coulomb interactions and spin-orbit effects influence electron transport in multi-level quantum dots, focusing on level splitting, Kondo ridge suppression, and g-factor dependence under magnetic fields.

Contribution

It provides a detailed analysis of the interplay between Coulomb repulsion and Rashba spin-orbit coupling in multi-level quantum dots, including experimental protocol comparisons.

Findings

Spin-orbit induced level splitting at finite Zeeman fields measured.

Suppression of Kondo ridges due to spin-orbit effects observed.

Renormalized g-factors depend on magnetic field orientation.

Abstract

We study electron transport through a multi-level quantum dot with Rashba spin-orbit interaction in the presence of local Coulomb repulsion. Motivated by recent experiments, we compute the level splitting induced by the spin-orbit interaction at finite Zeeman fields $B$, which provides a measure of the renormalized spin-orbit energy. This level splitting is responsible for the suppression of the Kondo ridges at finite $B$ characteristic for the multi-level structure. In addition, the dependence of renormalized $g$-factors on the relative orientation of the applied $B$ field and the spin-orbit direction following two different protocols used in experiments is investigated.