Linear Dichroism of the Dirac Cone on Sb2Te2S


The video shows the map of intensities for all measured k|| scanned through the measured energy range at a delay of 1000 fs.

The Dirac Cone is clearly visible in the ky|| direction. The Dirac point is 150 meV above the Fermi level. The conduction band minimum is around 400 meV above the Fermi level.

The right branch in kx|| of the Dirac cone is strongly pronounced in comparison to the left branch. This can be explained by a linear dichroism. For this measurement we used p-polarized light. By using s-polarized the asymmetry vanishes (see inset).