Abstract

Kondo insulators are emerging as a simplified setting to study both magnetic and insulator-to-metal quantum phase transitions. Here, we study the half-filled Anderson lattice model defined on a magnetically frustrated Shastry-Sutherland geometry. We determine a "global" phase diagram that applies to both the local-moment and intermediate-valence regimes. This provides the theoretical basis for understanding how tuning a Kondo insulator by external parameters can close its hybridization gap, liberate the local-moment spins from the conduction electrons, and lead to a magnetically correlated metal. We also calculate the momentum distribution of the single-particle excitations in the Kondo insulating state, and show how Fermi-surface-like features emerge as a precursor to the actual Fermi surfaces of the Kondo-destroyed metals. The implications for an incipient Fermi surface and quantum phase transitions of Kondo insulators including SmB6 are discussed.

Publication Details
Publication Type
Journal Article
Year of Publication
2018
Volume
98
DOI
10.1103/PhysRevB.98.085110
Journal
Physical Review B
Contributors
Groups