Fig. 5.

3D Fermi surface pockets and band structures. a Fermi surface pockets from ab initio calculations. Band structure along the direction of high-symmetry lines in the BZ (b) without and (c) spin–orbit coupling. Red circle along the H–K line labels the TP. The light blue circle along the H–Г line and the green circle along the H–D line labels the doubly degenerate points. Inset: Enlargement of the red rectangular boxes. The pink solid triangles (▲) and blue open squares (□) indicate the high-symmetry lines penetrating through the α and β pockets, respectively. d and e are magnified views of the blue-dashed rectangles in b and c, respectively. Bands are indicated by the relevant irreducible representations. f Spinless band along the H–K–Г–(−K)–(−H) line. g |A₁〉 state split into two different substates by taking into account the spin degree of freedom due to the breaking of spatial inversion symmetry