STM and STS investigations of Bi2Te3 surface

We carried out scanning tunneling microscopy/spectroscopy studies of Bi2Te3 surface, which, to the best of our knowledge, had not been attempted so far. We got images of surface of the material in many scales from micrometers to nanometers, which showed a layered structure of Bi2Te3, with many monoatomic terraces. We found agreement between measured heights and corresponding bulk crystal structure derived from X-ray data. In nanoscale we obtained an atomic resolution. Using scanning tunneling spectroscopy we carried out examination of the electronic structure. We observed different I-V characteristics and contrast on current imaging tunneling spectroscopy maps on non equivalent terraces. The dI/dV (similar to density of states) curves referred to those terraces were compared with theoretically calculated by Larson et al. density of states derived from Bi p and Te-1 p orbitals. The analysis of our results allowed us to distinguish bismuth from tellurium planes.