RKKY and magnetic field interactions in coupled Kondo quantum dots

TL;DR

This paper theoretically studies how RKKY interactions influence transport in coupled Kondo quantum dots, revealing magnetic field effects that distinguish interaction types and relate to recent experimental observations.

Contribution

It provides a theoretical analysis of RKKY and magnetic field effects on coupled Kondo quantum dots, highlighting distinguishable signatures for interaction types.

Findings

Impurity density of states increases with magnetic field under strong antiferromagnetic RKKY.

Magnetic field effects can differentiate between antiferromagnetic and ferromagnetic RKKY interactions.

Results relate to and potentially explain features observed in recent experiments.

Abstract

We investigate theoretically the transport properties of two independent artificial Kondo impurities. They are coupled together via a tunable Ruderman-Kittel-Kasuya-Yoshida (RKKY) interaction. For strong enough antiferromagnetic RKKY interaction, the impurity density of states increases with the applied in-plane magnetic field. This effect can be used to distinguish between antiferromagnetic and ferromagnetic RKKY interactions. These results may be relevant to explain some features of recent experiments by Craig et al. (cond-mat/0404213).