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arXiv · 0811.3220

Layered Kondo lattice model for quantum critical beta-YbAlB4

Andriy H. Nevidomskyy·P. Coleman
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Abstract

We analyze the magnetic and electronic properties of the quantum critical heavy fermion superconductor beta-YbAlB4, calculating the Fermi surface and the angular dependence of the extremal orbits relevant to the de Haas--van Alphen measurements. Using a combination of the realistic materials modeling and single-ion crystal field analysis, we are led to propose a layered Kondo lattice model for this system, in which two dimensional boron layers are Kondo coupled via interlayer Yb moments in a $J_{z}=\pm 5/2$ state. This model fits the measured single ion magnetic susceptibility and predicts a substantial change in the electronic anisotropy as the system is pressure-tuned through the quantum critical point.

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BibTeXRIS

Andriy H. Nevidomskyy, P. Coleman. 2009-03-11. Layered Kondo lattice model for quantum critical beta-YbAlB4. https://doi.org/10.1103/physrevlett.102.077202

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