Abstract
By combining scanning tunneling microscopy and spectroscopy, angle-resolved photoemission spectroscopy, and density functional theory band calculations, we directly observe and resolve the one-dimensional edge states of single bilayer (BL) Bi(111) islands on clean and Bi(111)-covered substrates. The edge states are localized in the vicinity of step edges having an wide spatial distribution in real space and reside in the energy gap of the Bi(111) BL. Our results demonstrate the existence of nontrivial topological edge states of single Bi(111) bilayer as a two-dimensional topological insulator.
- Received 26 February 2012
DOI:https://doi.org/10.1103/PhysRevLett.109.016801
© 2012 American Physical Society