Fig. 1: Electronic structure comparison between undoped and Co-doped 2H-TaS2.
a Crystal structure of Co1/3TaS2. Adjacent TaS2 layers with opposite in-plane orientations are highlighted in orange and yellow. b Top view of the crystal structure. The solid and dashed black lines represent the unit cells of Co1/3TaS2 and 2H-TaS2, respectively. c Phase diagram of Co1/3TaS2, adapted from ref. 20. d Top view of the 3Q magnetic order on a triangular lattice. The black lines indicate the magnetic unit cell. e, f Low temperature (7 K) Fermi surfaces mapping of 2H-TaS2 and Co0.32TaS2. The solid (dashed) lines denote the Brillouin zone of 2H-TaS2 (Co1/3TaS2). High-symmetry points are labeled as Γ0, K0, and M0 for 2H-TaS2, and Γ, K, and M for Co1/3TaS2. The gapped portion indicated by an arrow signifies the charge density wave (CDW) gap in 2H-TaS2. In both panels, the fitted Fermi surfaces obtained from the raw data are overlaid in the upper-left quadrants. Observed Fermi surface sheets are marked with α (dark blue curves), β (light blue curves) and γ (magenta curves). Energy-momentum intensity plots of 2H-TaS2 (g) and Co0.32TaS2 (h, i), measured along the M0-Γ0-K0 high-symmetry direction. Data in (g, h) are acquired using linearly horizontally (LH) polarized light, whereas (i) uses linearly vertically (LV) polarized light. j, k Extracted band dispersions of 2H-TaS2 (α, β and δ) and Co0.32TaS2 (α, β, γK, γM and ϵ), together with the corresponding momentum distribution curves (MDCs) at the Fermi level (EF). Filled and open circles denote the peak positions of MDCs and energy distribution curves (EDCs), respectively, extracted from Supplementary Fig. S2. l Calculated band structures including spin-orbit coupling along M0-Γ0-K0 in the kz = 0 plane for bulk 2H-TaS2. The Fermi level of Co0.32TaS2 is referenced by shifting EF upward by 300 meV.
