Investigation of Surface Magnetism in Systems Based on MnBi2Te4 Using the Magneto-Optical Kerr Effect

D. A. Glazkova, D. A. Estyunin, A. S. Tarasov, N. N. Kosyrev, V. A. Komarov, G. S. Patrin, V. A. Golyashov, O. E. Tereshchenko, K. A. Kokh, A. V. Koroleva & A. M. Shikin // Crystallography Reports//

MnBi2Te4, Mn(Bi,Sb)2Te4, and MnBi2Te4(Bi2Te3)m (m ≥ 1) are assigned to magnetic topological insulators. Successful application of these materials in nanoelectronic devices calls for comprehensive investigation of their electronic structure and magnetic properties in dependence of the Bi/Sb atomic ratio and the number m of Bi2Te3 blocks. The magnetic properties of the surface of MnBi2Te4, MnBi4Te7, and Mn(Bi1−�Sbx)2Te4 compounds (x = 0.43 and 0.32) have been studied using the magneto-optical Kerr effect. It is shown that the temperatures of magnetic transitions on the surface and in the bulk of MnBi4Te7 and Mn(Bi, Sb)2Te4 differ significantly.