Physics and Astronomy, Ames Laboratory
Journal or Book Title
The antiferromagnetic (AF) compound MnBi2Te4 is suggested to be the first realization of an antiferromagnetic (AF) topological insulator. Here we report on inelastic neutron scattering studies of the magnetic interactions in MnBi2Te4 that possess ferromagnetic (FM) triangular layers with AF interlayer coupling. The spin waves display a large spin gap and pairwise exchange interactions within the triangular layer are frustrated due to large next-nearest neighbor AF exchange. The degree of frustration suggests proximity to a variety of magnetic phases, potentially including skyrmion phases, that could be accessed in chemically tuned compounds or upon the application of symmetry-breaking fields.
Yan, J.-Q.; Pajerowski, D.; Ke, Liqin; Nedic, Ana-Marija; Sizyuk, Y.; Gordon, Elijah; Orth, Peter P.; Vaknin, David; and McQueeney, Robert J., "Competing magnetic interactions in the antiferromagnetic topological insulator MnBi2Te4" (2019). Physics and Astronomy Publications. 518.