Surface state of the dual topological insulator Bi0.91Sb0.09(112¯)

The electronic structure of a Bi0.91Sb0.09 single crystal was elucidated at a bisectrix (112¯) surface by angle-resolved photoemission spectroscopy using microbeam synchrotron radiation. A Dirac-cone-like dispersion of the surface state was observed at the Γ¯ point. The detected surface-state band likely corresponds to the one observed in previous quantum transport research (Taskin and Ando, 2009) [14].