Magnetic topological Kondo semimetal phases of matter

Abstract

Kondo physics has long been interesting for studying correlated topology in isolation, as it occurs in heavy fermion compounds where myriad phenomena are well-separated in energy. We introduce magnetic topological Kondo semimetal phases of matter into the literature in this work to advance the understanding of correlated topological semimetal physics by studying a layered three-dimensional heterostructure in which two types of Kondo insulators are stacked alternatingly. In the heterostructures considered, one of these Kondo insulators is SmB6, a potential topological Kondo insulator, and the other one is an isostructural Kondo insulator AB6, where A is a rare-earth element, e.g., Eu, Yb, or Ce. We find that if the latter Kondo insulator orders ferromagnetically, the heterostructure generically becomes a magnetic Weyl Kondo semimetal, while antiferromagnetic order can yield a magnetic Dirac Kondo semimetal. We also confirm the realization of the magnetic Weyl (Dirac) Kondo semimetal phase in density functional theory calculations of the heterostructure of SmB6 and EuB6 (CeB6). Our results demonstrate that Kondo insulator heterostructures are a versatile platform for realizing correlated topological semimetal phases.