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arXiv · 1212.1783

Spin-polarized (001) surface states of the topological crystalline insulator Pb_{0.73}Sn_{0.27}Se

B. M. Wojek·R. Buczko·S. Safaei·P. Dziawa·B. J. Kowalski·M. H. Berntsen·T. Balasubramanian·M. Leandersson·A. Szczerbakow·P. Kacman·T. Story·O. Tjernberg
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Abstract

We study the nature of (001) surface states in Pb_{0.73}Sn_{0.27}Se in the newly discovered topological-crystalline-insulator (TCI) phase as well as the corresponding topologically trivial state above the band-gap-inversion temperature. Our calculations predict not only metallic surface states with a nontrivial chiral spin structure for the TCI case, but also nonmetallic (gapped) surface states with nonzero spin polarization when the system is a normal insulator. For both phases, angle- and spin-resolved photoelectron spectroscopy measurements provide conclusive evidence for the formation of these (001) surface states in Pb_{0.73}Sn_{0.27}Se, as well as for their chiral spin structure.

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B. M. Wojek, R. Buczko, S. Safaei, P. Dziawa, B. J. Kowalski, M. H. Berntsen, T. Balasubramanian, M. Leandersson, A. Szczerbakow, P. Kacman, T. Story, O. Tjernberg. 2012-12-08. Spin-polarized (001) surface states of the topological crystalline insulator Pb_{0.73}Sn_{0.27}Se. https://doi.org/10.1103/physrevb.87.115106

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