Fig. 1: Electronic structure and optical properties of topological kagome magnet TbMn6Sn6.
a Schematic illustration of the massive Dirac fermions arising from the kagome lattice with the out-of-plane magnetic moment. b Crystal structure of TbMn6Sn6. The Tb and Mn spins are ferrimagnetically ordered as indicated by red and blue arrows. c The kagome network formed by the Mn atoms (upper panel) and schematic of the Mn 3dxy orbital lying within ab plane (lower panel). The local coordinates for the xy orbital are indicated in the upper panel. d The DFT calculation. See Supplementary Fig. 2 for the definition of high-symmetry points in Brillouin zone. The color bar shown in the right side represents the weight of the Mn 3dxy orbital. The purple dotted curve highlights the massive Dirac band. The light blue arrow denotes the lowest-energy interband transition within the massive Dirac band, which causes the enhanced MO effects. e Temperature dependence of optical conductivity spectra in the kagome plane σxx(ω). f Temperature dependence of the Kerr rotation spectra θK(ω) for the kagome plane.
