Half-Heusler Compounds as a New Class of Three-Dimensional Topological Insulators

Abstract

Using first-principles calculations within density functional theory, we explore the feasibility of converting ternary half-Heusler compounds into a new class of three-dimensional topological insulators (3DTI). We demonstrate that the electronic structure of unstrained LaPtBi as a prototype system exhibits distinct band-inversion feature. The 3DTI phase is realized by applying a uniaxial strain along the [001] direction, which opens a bandgap while preserving the inverted band order. A definitive proof of the strained LaPtBi as a 3DTI is provided by directly calculating the topological Z2 invariants in systems without inversion symmetry. We discuss the implications of the present study to other half-Heusler compounds as 3DTI, which, together with the magnetic and superconducting properties of these materials, may provide a rich platform for novel quantum phenomena.

4 pages, 5 figures; Phys. Rev. Lett. (in press)

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Cited by in corpus (7)

• Computing topological invariants without inversion symmetry
• Half-Heusler Topological Insulators: A First-Principle Study with the Tran-Blaha Modified Becke-Johnson Density Functional
• Three-Dimensional Topological Insulators in I-III-VI${}_2$ and II-IV-V${}_2$ Chalcopyrite Semiconductors
• Metallic surface electronic state in half-Heusler compounds RPtBi (R = Lu, Dy, Gd)
• Surface and Edge States in Topological Semi-metals
• Anomalous Hall response of topological insulators
• Manifestly gauge independent formulations of the Z2 invariants