Surface state of the dual topological insulatorBi0.91Sb0.09(112¯)

The electronic structure of a Bi 0.91 Sb 0.09 single crystal was elucidated at a bisectrix ( 11 2 ¯ ) 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].