Real-space observation of magnetic transitions in RMn6Sn6 (R = Ho, Dy) kagome magnets

Rare-earth RMn6Sn6 magnets reattract the attention due to their recently discovered topological properties in a strong correlation with a kagome magnetic lattice and different rare-earth magnetic elements. To understand the microscopic mechanism and discover topological spin textures, we report here the real-space observation of temperature-induced spin reorientation transition in RMn6Sn6 (R = Ho, Dy) magnets. The magnetic domain evolution corresponding to the magnetization deviation from the ab-plane into a cone state is in situ demonstrated by using Lorenz transmission electron microscopy and, moreover, individual biskyrmions are generated at room temperature under an external magnetic field in DyMn6Sn6.