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

Kevin Ingersent·Andreas W. W. Ludwig·Ian Affleck
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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.

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Kevin Ingersent, Andreas W. W. Ludwig, Ian Affleck. 2005-12-18. Kondo screening in a magnetically frustrated nanostructure: Exact results on a stable, non-Fermi-liquid phase. https://doi.org/10.1103/physrevlett.95.257204

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