Experimental realization of a topological crystalline insulator in SnTe

By Yukio Tanaka, Z. Ren, Takafumi Sato, K. Nakayama, S. Souma, Takashi Takahashi, K. Segawa, Y. Ando. Nature Physics, 2012

818 citations recorded by the source corpus.

A topological insulator has surface metallic states that are topologically protected by time-reversal symmetry. Tin telluride is now shown to be a ‘topological crystalline insulator’, in which the surface metallic state is instead protected by the mirror symmetry of the crystal. A topological insulator is an unusual quantum state of matter, characterized by the appearance, at its edges or on its surface, of a gapless metallic state that is protected by time-reversal symmetry1,2. The discovery of topological insulators has stimulated the search for other topological states protected by other symmetries3,4,5,6,7, such as the recently predicted8 topological crystalline insulator (TCI) in which the metallic surface states are protected by the mirror symmetry of the crystal. Here we present experimental evidence for the TCI phase in tin telluride (SnTe), which has been predicted to be a TCI (ref. 9). Our angle-resolved photoemission spectra show the signature of a metallic Dirac-cone surface band, with its Dirac point slightly away from the edge of the surface Brillouin zone in SnTe. Such a gapless surface state is absent in a cousin material, lead telluride, in line with the theoretical prediction.

Subfields: Atomic and Molecular Physics, and Optics, Condensed Matter Physics, Materials Chemistry

View Paper: https://www.semanticscholar.org/paper/098600f0a6c7d5c2dafe53bfc8a9c2088f7e7f9f

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Atomic and Molecular Physics, and Optics

1. Ashvin Vishwanath
2. Y. Ando
3. E. Khalaf
4. D. Vanderbilt
5. Hsin Lin
6. Arun Bansil
7. Masatoshi Sato
8. H. Po

In Condensed Matter Physics

1. Ashvin Vishwanath
2. Y. Ando
3. E. Khalaf
4. Masatoshi Sato
5. H. Po
6. Su-Yang Xu
7. M. Zahid Hasan
8. Hsin Lin

In Materials Chemistry

1. Ashvin Vishwanath
2. E. Khalaf
3. Hsin Lin
4. Arun Bansil
5. Y. Ando
6. Tanmoy Das
7. H. Po
8. Masatoshi Sato

Citations in the corpus

• Colloquium : Topological band theory (2016, background): “(Dziawa et al. 2012; Tanaka et al. 2012; Xu, Liu, et al. 2012) The Dirac cone structure and the associated spin-texture of surface states in a TCI is quite distinct from that in the more common TIs.”
• Symmetry Indicators and Anomalous Surface States of Topological Crystalline Insulators (2017, background): “Such is the case for the 3D phases like weak TI [1], the mirror Chern insulator [6,7], and the nonsymmorphic insulators featuring so-called hourglass”
• Z2Pack: Numerical Implementation of Hybrid Wannier Centers for Identifying Topological Materials (2016, background): “A TR-symmetric example of a mirror-symmetric crystalline topological insulator is SnTe, in which the topological phase is protected by the mirror symmetry of its rocksalt structure [122,123].”
• Topological superconductors: a review (2016, background): “For example, in the case of insulators, SnTe hosts gapless surface states ensured by a nonzero mirror Chern number, while it is trivial in the Z2 topology [77, 78].”
• First principles design of spintronics materials (2016, methodology): “Bulk SnTe is the first TCI that was proposed based on first-principles calculations [100], and verified by a subsequent experiment [101].”