Topological crystalline insulators represent a novel topological phase of matter in which the surface states are protected by discrete point group-symmetries of the underlying lattice. Rock-salt lead-tin-selenide alloy is one possible realization of this phase which undergoes a topological phase transition upon changing the lead content. We used scanning tunneling microscopy (STM) and angle resolved photoemission spectroscopy (ARPES) to probe the surface states on (001) Pb1−xSnxSe in the topologically non-trivial (x=0.23) and topologically trivial (x=0) phases. We observed quasiparticle interference with STM on the surface of the topological crystalline insulator and demonstrated that the measured interference can be understood from ARPES studies and a simple band structure model. Furthermore, our findings support the fact that Pb0.77Sn0.23Se and PbSe have different topological nature.
@article{arxiv.1306.0043,
title = {Quasiparticle Interference on the Surface of Topological Crystalline Insulator Pb(1-x)Sn(x)Se},
author = {A. Gyenis and I. K. Drozdov and S. Nadj-Perge and O. B. Jeong and J. Seo and I. Pletikosic and T. Valla and G. D. Gu and A. Yazdani},
journal= {arXiv preprint arXiv:1306.0043},
year = {2013}
}