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arXiv · 1207.6441

β-YbAlB4: a critical nodal metal

Aline Ramires·Piers Coleman·Andriy H. Nevidomskyy·A. M. Tsvelik
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Abstract

We propose a model for the intrinsic quantum criticality of β-YbAlB4, in which a vortex in momentum space gives rise to a new type of Fermi surface singularity. The unquenched angular momentum of the |J = 7/2,m_J = \pm5/2> Yb 4f-states generates a momentum-space line defect in the hybridization between 4f and conduction electrons, leading to a quasi-two dimensional Fermi surface with a k\perp4 dispersion and a singular density of states proportional to E^{-1/2}. We discuss the implications of this line-node in momentum space for our current understanding of quantum criticality and its interplay with topology.

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Aline Ramires, Piers Coleman, Andriy H. Nevidomskyy, A. M. Tsvelik. 2012-07-27. β-YbAlB4: a critical nodal metal. https://doi.org/10.1103/physrevlett.109.176404

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