We report the evolution of the surface electronic structure and surface material properties of a topological crystalline insulator (TCI) Pb1-xSnxSe as a function of various material parameters including composition x, temperature T and crystal structure. Our spectroscopic data demonstrate the electronic groundstate condition for the saddle point singularity, the tunability of surface chemical potential, and the surface states' response to circularly polarized light. Our results show that each material parameter can tune the system between trivial and topological phase in a distinct way unlike as seen in Bi2Se3 and related compounds, leading to a rich and unique topological phase diagram. Our systematic studies of the TCI Pb1-xSnxSe are valuable materials guide to realize new topological phenomena.
@article{arxiv.1508.05886,
title = {Topological phase diagram and saddle point singularity in a tunable topological crystalline insulator},
author = {Madhab Neupane and Su-Yang Xu and R. Sankar and Q. Gibson and Y. J. Wang and I. Belopolski and N. Alidoust and G. Bian and P. P. Shibayev and D. S. Sanchez and Y. Ohtsubo and A. Taleb-Ibrahimi and S. Basak and W. -F. Tsai and H. Lin and Tomasz Durakiewicz and R. J. Cava and A. Bansil and F. C. Chou and M. Zahid Hasan},
journal= {arXiv preprint arXiv:1508.05886},
year = {2015}
}
Comments
10 pages, 7 figures. Expanded version of arXiv:1403.1560