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arXiv · 1609.04023

Filling-enforced Kondo semimetals in two-dimensional non-symmorphic crystals

J. H. Pixley·SungBin Lee·B. Brandom·S. A. Parameswaran
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Abstract

We study the competition between Kondo screening and frustrated magnetism on the non-symmorphic Shastry-Sutherland Kondo lattice at a filling of two conduction electrons per unit cell. A previous analysis of this model identified a set of gapless partially Kondo screened phases intermediate between the Kondo-destroyed paramagnet and the heavy Fermi liquid. Based on crystal symmetries, we argue that (i)~both the paramagnet and the heavy Fermi liquid are {\it semimetals} protected by a glide symmetry; and (ii)~partial Kondo screening breaks the symmetry, removing this protection and allowing the partially-Kondo-screened phase to be deformed into a Kondo insulator via a Lifshitz transition. We confirm these results using large-$N$ mean field theory and then use non-perturbative arguments to derive a generalized Luttinger sum rule constraining the phase structure of 2D non-symmorphic Kondo lattices beyond the mean-field limit.

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J. H. Pixley, SungBin Lee, B. Brandom, S. A. Parameswaran. 2016-09-13. Filling-enforced Kondo semimetals in two-dimensional non-symmorphic crystals. https://doi.org/10.1103/physrevb.96.081105

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