Topological Materials
Hsin Lin1*
1Institute of Physics, Academia Sinica, Taipei, Taiwan
* Presenter:Hsin Lin,
Topological materials host various novel quantum phases of electrons which are characterized by band topology and topologically protected surface/edge states.[1] Despite recent progress, intense world-wide research activity in search of new classes of topological materials is continuing unabated. This interest is driven by the need for materials with greater structural flexibility and tunability to enable viable applications in spintronics and quantum computing. We have used first-principles band theory computations to successfully predict many new classes of 3D topologically interesting materials, including Bi2Se3 series,[2] the ternary half-Heusler compounds, TlBiSe2 family, Li2AgSb-class, and GeBi2Te4 family as well as topological crystalline insulator (TCI) SnTe family[3] and Weyl semimetals TaAs,[4-5] SrSi2, (Mo,W)Te2, Ta3S2, and LaAlGe family. I will also highlight our recent work on unconventional chiral fermions in RhSi compounds.[6]

[1] A. Bansil, H. Lin, and T. Das, “Colloquium : Topological band theory,” Rev. Mod. Phys. 88, 021004 (2016).
[2] Y. Xia et al., “Observation of a large-gap topological-insulator class with a single Dirac cone on the surface,” Nat. Phys. 5, 398–402, (2009).
[3] T. H. Hsieh, H. Lin, J. Liu, W. Duan, A. Bansi, and L. Fu, “Topological crystalline insulators in the SnTe material class,” Nat. Commun. 3, 982, (2012).
[4] S.-M. Huang et al., “A Weyl Fermion semimetal with surface Fermi arcs in the transition metal monopnictide TaAs class,” Nat. Commun. 6, 7373, (2015).
[5] S.-Y. Xu et al., “Discovery of a Weyl fermion semimetal and topological Fermi arcs,” Science, 349, 613–617, (2015).
[6] G. Chang et al., “Unconventional chiral fermions and large topological Fermi arcs in RhSi,” Phys. Rev. Lett., (2017).

Keywords: topological insulator, Weyl semimetal, first-principles calculations