Exchange Bias in Magnetic Topological Insulator Superlattices.

ABSTRACT: Magnetic doping and proximity coupling can open a band gap in a topological insulator (TI) and give rise to dissipationless quantum conduction phenomena. Here, by combining these two approaches, we demonstrate a novel TI superlattice structure that is alternately doped with transition and rare earth elements. An unexpected exchange bias effect is unambiguously confirmed in the superlattice with a large exchange bias field using magneto-transport and magneto-optical techniques. Further, the Curie temperature of the Cr-doped layers in the superlattice is found to increase by 60 K compared to a Cr-doped single-layer film. This result is supported by density-functional-theory calculations, which indicate the presence of antiferromagnetic ordering in Dy:Bi₂Te₃ induced by p

SUBMITTER: Liu J 

PROVIDER: S-EPMC7467763 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature