Extended Data Fig. 4: Analysis of the helicoid arc dispersion in CoSi.
From: Tunable topologically driven Fermi arc van Hove singularities
a, b, Surface-sensitive ARPES measured Fermi surface map of CoSi and corresponding 2D curvature plot (panel b). The purple (Cut A) and green (Cut B) dashed lines illustrate the orthogonal paths of interest. c, d, Raw ARPES measured energy-momentum cut along Cut A and corresponding 2D curvature plot (panel d). e, f, Raw ARPES measured energy-momentum cut along Cut B and corresponding 2D curvature plot (panel f). The red circles in panels (d) and (f) obtain from a standard Lorentzian fitting procedure of the photoemission intensity at various energies along the kA and kB direction, respectively. Error bars for the extracted points are ± 0.05 Å−1 ( ± 0.08 Å−1) along the kA (kB) axis.
