We have performed systematic angle-resolved photoemission spectroscopy of the topological crystalline insulator (TCI) Pb1-xSnxTe to elucidate the evolution of its electronic states across the topological phase transition. As previously reported, the band structure of SnTe (x=1.0) measured on the (001) surface possesses a pair of Dirac-cone surface states located symmetrically across the X̄ point in the (110) mirror plane. Upon approaching the topological phase transition into the trivial phase at x c≈0.25, we discovered that Dirac cones gradually move toward the X̄ point with its spectral weight gradually reduced with decreasing x. In samples with x≤0.2, the Dirac-cone surface state is completely gone, confirming the occurrence of the topological phase transition. Also, the evolution of the valence band feature is found to be consistent with the bulk band inversion taking place at xc. The tunability of the location of the Dirac cones in the Brillouin zone would be useful for applications requiring Fermi-surface matching with other materials, such as spin injection.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - 2013 Apr 2|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics