Kondo screening in a magnetically frustrated nanostructure: Exact results on a stable, non-Fermi-liquid phase

TL;DR

This paper investigates a stable, non-Fermi-liquid phase in a three-impurity Kondo model with triangular symmetry, providing exact results and universal properties, with potential experimental signatures.

Contribution

It identifies a novel non-Fermi-liquid phase stabilized by geometric frustration, supported by conformal field theory and numerical renormalization group analysis, without fine-tuning.

Findings

Discovery of a stable non-Fermi-liquid phase due to frustration

Exact universal low-energy properties derived

Predicted experimental signatures in transport measurements

Abstract

Triangular symmetry stabilizes a novel non-Fermi-liquid phase in the three-impurity Kondo model with frustrating antiferromagnetic interactions between half-integer impurity spins. The phase arises without fine-tuning of couplings, and is stable against magnetic fields and particle-hole symmetry breaking. We find a conformal field theory describing this phase, verify it using the numerical renormalization group, and extract various exact, universal low-energy properties. Signatures predicted in electrical transport may be testable in scanning tunneling microscopy or quantum-dot experiments.