An Intrinsically Magnetic Topological Insulator

Topological insulators that are intrinsically magnetic—rather than made to have a field by the incorporation of magnetic impurities—may provide opportunities to study how magnetism affects these materials’ distinctive electron-transport properties. Researchers have recently shown that the topological insulator manganese bismuth telluride (MnB2Te4) is naturally magnetically ordered in its interior, but they had not determined whether this bulk ferromagnetism extends to the surface. Now, Dan Nevola of Brookhaven National Laboratory, New York, and colleagues have experimentally confirmed that MnBi2Te4 is magnetically ordered at its surface as well [1].