Extended Data Fig. 2: Majorana cones and hinge states from effective model description.

(a) Energy gap as a function of the dimensionless momenta k_x and k_y in a slab geometry, finite in the z direction. The projections of the Weyl cones are connected pairwise by two weakly-gapped Fermi arcs, one on the top surface and one on the bottom surface. (b) Closeup showing two Weyl cone projections (green arrows), a Majorana cone on the bottom surface (blue arrow), and a Majorana cone on the top surface (orange arrow). (c) Gap along the Fermi arc on the top surface. An out-of-plane Zeeman field gaps out the Majorana cone, enhancing the SC gap. Blue, orange, green, and red curves correspond to increasing Zeeman fields V_z = 0, 0.05, 0.1, and 0.15, respectively. (d) Bandstructure of the system in a prism geometry, infinite along y, and finite along x and z, plotted for the values of k_y between the two green dashed lines of panel (a). This panel appears also in the main text. The color scale denotes the probability density of the states in real space. Bulk Weyl cones are shown in green, and top and bottom Majorana cones are shown in red and blue, respectively. Dispersionless zero-energy Majorana hinge modes are shown in black.