Fig. 2: Electronic band structure of BaMnSb₂.

a The band structure from the first-principles calculation, with the inset showing the first BZ and red dots labeling the two gapped Dirac cones at \({K}_{\pm }\). b the calculated Dirac band dispersion near \({K}_{+}\) and \({K}_{-}\), with the spin projection being color-coded (red, spin-up; blue, spin-down). c Schematic illustration of the orbital evolution at \({K}_{+}\). Here \({p}_{\pm }=(p_{x}\pm i{p}_{y})/\sqrt{2}\); all orbitals come from Sb2 (see Fig. 1b) and the two bases in the black dashed box form the gapped Dirac cone. d Constant energy contour of Ba(Mn_0.9Zn_0.1)Sb₂ on the k_x–k_y plane, which is acquired by integrating the intensity from −15 to −5 meV. The ARPES data was taken with the photon energy of 30 eV. Two point-like hole pockets near \(\bar{{\rm{X}}}\) point can be seen. The presence of hole pockets near \(\bar{{\rm{Y}}}\) point is due to twin domains. e ARPES spectrum along \(\bar{\Gamma }\bar{{\rm{X}}}\) (cut 1 in panel d). There is only one crossing point near the Fermi level (E_F) at \(\bar{{\rm{X}}}\)/\(\bar{{\rm{Y}}}\). f ARPES spectrum along \(\bar{{\rm{M}}}\bar{{\rm{X}}}\) (cut 2 in panel d). Two crossing points at E_F can be clearly resolved near \(\bar{{\rm{X}}}\)/\(\bar{{\rm{Y}}}\). g Comparison of the calculated band (dotted lines) and the band probed by ARPES along \(\bar{{\rm{M}}}\bar{{\rm{X}}}\) (cut 2 in panel d).