Fig. 1: Crystal lattice and electronic band structure of Fe₂Ge₃.

a Crystal structure of Fe₂Ge₃ single crystal. The pink and purple balls represent Fe and Ge atoms. b Scanning electron microscope image of the Fe₂Ge₃ crystal and the diffraction spots observed with X-ray single-crystal diffraction at 293 K in three different orientations. c X-ray diffraction and Laue diffraction pattern along the a-axis of Fe₂Ge₃. d The temperature (T) dependence of transverse resistivity ρ_xx at zero magnetic field. Inset: low-temperature data fitted to ρ = ρ₀ + aT², where residual resistance ρ₀ is the resistance when T tends to 0 K and a is the constant. e Electronic energy band structure of Fe₂Ge₃ obtained from first principles calculations. The vertical coordinate is the energy difference of the electron energy with respect to the Fermi energy level and the energy coordinate is the point of high symmetry in crystal momentum space (f) Orbital projected electronic energy band structure and the symbol size is positively related to the density of states. g Density of states (DOS). The inset shows the Brillion zone of the tetragonal structure.