Discovery of topological insulators about a decade ago caused a global research boom in the fields of nanotechnology and condensed matter physics. One of the challenges during these years of intense research has been the creation of a magnetic topological insulator. Until recently, magnetic topological insulators had only been created by the so-called extrinsic route, which consists of doping nonmagnetic topological insulators with magnetic atoms. The situation had been changed dramatically with a discovery of the first intrinsic topological insulator MnBi2Te4 (Otrokov et al., Nature, 2019) and related compounds family (Klimovskikh et al., npj Quantum Materials, 2020). In this report I review the details of crystal, magnetic and electronic structure of these new materials. Depending on the stoichiometry and thickness a rich variety of magnetic and topological phases is realized. The hot topic of presence/absence of the Dirac point band gap at the surface will be discussed. The experiment will be compared with density functional theory results; possibilities of applications for quantized transport, quantum computers and dark matter detector will be analyzed.
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