Filling-enforced nonsymmorphic Kondo semimetals in two dimensions

Article

关键词: QUANTUM PHASE-TRANSITIONS;    HEAVY-FERMION METALS;    CRITICALITY;    DIAGRAM;    SURFACE;    LIQUIDS;    LATTICE;   

DOI  :  10.1103/PhysRevB.96.081105

来源: SCIE

【 摘 要 】

We study the competition between Kondo screening and frustrated magnetism on the nonsymmorphic Shastry-Sutherland Kondo lattice at a filling of two conduction electrons per unit cell. This model is known to host 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 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 nonperturbative arguments to derive a generalized Luttinger sum rule constraining the phase structure of two-dimensional nonsymmorphic Kondo lattices beyond the mean-field limit.

【 授权许可】

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