Extended Data Fig. 4: Topological band features of CaRh2.
From: Three-dimensional flat bands in pyrochlore metal CaNi2
(a) The ARPES spectrum of Ca(Rh0.98Ru0.02)2 along the Γ-K-X direction measured with 127 eV photons. The flat band corresponds to the FB2 in CaNi2 and the dispersive band with band top at Γ are marked with black arrows. Detailed dispersions of the flat band and the dispersive band are obtained from the corresponding EDC analyses in (c) and overlaid on top of the ARPES spectrum in (a). The double-headed arrows in (a) and (c) indicate the SOC gap between the flat band and the dispersive band. (b) DFT band structure of CaRh2 for comparison with the experimental dispersions in (a),(c). (d,e) Wide energy-range ARPES spectrum of Ca(Rh0.98Ru0.02)2 and its second derivative plot measured along the Γ-K-X direction. (f) DFT band structure of CaRh2 for comparison with (d,e). The red arrows in (d-f) mark the symmetry-protected Dirac crossing at X.
