A first-principles investigation of Topological Phase Transition in face-centred cubic LiMgBi

Abstract

Topological Insulators (TI) exhibit robust spin-locked dissipationless Fermion transport along the surface states. In the current study, we use \textit{first-principles} calculations to investigate a Topological Phase Transition (TPT) in a Half-Heusler (HH) compound LiMgBi driven by a Volume Expansive Pressure (VEP) which is attributed to the presence of, intrinsic voids, thermal perturbations and/or due to a phenomena known as cavity nuclei. We find that, the dynamically stable \textit{face-centred cubic} (FCC) structure of LiMgBi (which belongs to the F$\overline{4}$3m[216] space group), undergoes TPT beyond a critical VEP at 4.0\%. The continuous application of VEP from 0.0\% to 8.0\% results in a phase transition from a, band insulator to a Dirac semi-metal nature. Qualitatively, the Dirac cone formation and band inversion along the high symmetry point $\mathbf{\Gamma }$ in the Brillouin Zone (BZ) are analysed in terms of Electronic Band Structure (EBS) and Projected Local Density of States (LDOS). The TPT is further characterised by the ${\mathbb{Z}}_2$ invariant, (${\nu }_0$, ${\nu }_1$ ${\nu }_2$ ${\nu }_3$) $\equiv$ (1, 0 0 0) along the (0001) surface which indicates quantitatively that, HH LiMgBi is a strong TI. We hence propose, HH LiMgBi (known for its piezoelectric, thermo-electric and semi-conducting applications) as a strong TI with potential multipurpose application in the field of electronics, spintronics and quantum computation.

arXiv comment21 pages, 12 figures

References in corpus (23)

• Topological Insulators
• Topological insulators and superconductors
• Phonons and related properties of extended systems from density-functional perturbation theory
• Electronic Structure of Pyrochlore Iridates: From Topological Dirac Metal to Mott Insulator
• Topological Insulators in Three Dimensions
• Discovery (theoretical prediction and experimental observation) of a large-gap topological-insulator class with spin-polarized single-Dirac-cone on the surface
• An equivalent expression of Z2 Topological Invariant for band insulators using Non-Abelian Berry's connection
• Topological Nodal Line Semimetal and Dirac Semimetal State in Antiperovskite Cu${}_3$PdN
• Topological Node-Line Semimetal in Three Dimensional Graphene Networks
• A new platform for topological quantum phenomena : Topological Insulator states in thermoelectric Heusler-related ternary compounds
• Computing topological invariants without inversion symmetry
• Band structure engineering in (Bi1-xSbx)2Te3 ternary topological insulators
• Half-Heusler Compounds as a New Class of Three-Dimensional Topological Insulators
• Half-Heusler semiconductors as piezoelectrics
• Quantum spin Hall effect in three dimensional materials: Lattice computation of Z${}_2$ topological invariants and its application to Bi and Sb
• Dirac node lines in pure alkali earth metals
• 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)
• Theoretical search for half-Heusler topological insulators
• Strain tuning of topological band order in cubic semiconductors
• Antiferroelectric topological insulators in orthorhombic $A$MgBi compounds ($A=$ Li, Na, K)
• Strain induced ${\mathbb{Z}}_2$ topological insulating state of $\beta$-As${}_2$Te${}_3$
• Screening potential topological insulators in half-Heusler compounds via compressed-sensing