Highly-ordered wide bandgap materials for quantized anomalous Hall and magnetoelectric effects

Abstract

An interplay of spin-orbit coupling and intrinsic magnetism is known to give\nrise to the quantum anomalous Hall and topological magnetoelectric effects\nunder certain conditions. Their realization could open access to low power\nconsumption electronics as well as many fundamental phenomena like image\nmagnetic monopoles, Majorana fermions and others. Unfortunately, being realized\nvery recently, these effects are only accessible at extremely low temperatures\nand the lack of appropriate materials that would enable the temperature\nincrease is a most severe challenge. Here, we propose a novel material platform\nwith unique combination of properties making it perfectly suitable for the\nrealization of both effects at elevated temperatures. The key element of the\ncomputational material design is an extension of a topological insulator (TI)\nsurface by a thin film of ferromagnetic insulator, which is both structurally\nand compositionally compatible with the TI. Following this proposal we suggest\na variety of specific systems and discuss their numerous advantages, in\nparticular wide band gaps with the Fermi level located in the gap.\n