Fig. 2: Relativistic electronic structure of NiTa₃S₆.

a Band structure calculated for the nonmagnetic phase (left-hand panel), and the representative Fermi sheets (right-hand panels). The narrow cylindrical sheet corresponds to the innermost band, while the larger sheet below originates from one of the outermost bands. Note that the inequivalent high-symmetry points H⁺ and H⁻ are different from those in the nonrelativistic magnetic phase shown in Fig. 1. b Same as (a) but calculated for the altermagnetic phase with the Néel vector along the [001] direction. The color of the bands represents the S_z projection of spin texture; S_x and S_y are negligible and they are not shown. Note that the inequivalent high-symmetry points are different from those in Fig. 1. The full set of Fermi surfaces for both phases is provided in the Supplementary Information.