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Exploring strong and weak topological states on isostructural substitutions in TlBiSe[Formula: see text].

ABSTRACT: Topological Insulators (TIs) are unique materials where insulating bulk hosts linearly dispersing surface states protected by the Time-Reversal Symmetry. These states lead to dissipationless current flow, which makes this class of materials highly promising for spintronic applications. Here, we predict TIs by employing state-of-the-art first-principles based methodologies, viz., density functional theory and many-body perturbation theory (G[Formula: see text]W[Formula: see text]) combined with spin-orbit coupling effects. For this, we take a well-known 3D TI, TlBiSe[Formula: see text] and perform complete substitution with suitable materials at different sites to check if the obtained isostructural materials exhibit topological properties. Subsequently, we scan these materials based on SOC-induced parity inversion at Time-Reversal Invariant Momenta. Later, to confirm the topological nature of selected materials, we plot their surface states along with calculation of Z[Formula: see text] invariants. Our results show that GaBiSe[Formula: see text] is a strong Topological Insulator, besides, we report six weak Topological Insulators, viz., PbBiSe[Formula: see text], SnBiSe[Formula: see text], SbBiSe[Formula: see text], Bi[Formula: see text]Se[Formula: see text], TlSnSe[Formula: see text] and PbSbSe[Formula: see text]. We have further verified that all the reported TIs are dynamically stable, showing all real phonon modes of vibration.

SUBMITTER: Phutela A

PROVIDER: S-EPMC9767939 | biostudies-literature | 2022 Dec

REPOSITORIES: biostudies-literature

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Exploring strong and weak topological states on isostructural substitutions in TlBiSe[Formula: see text].

Phutela Ankita A Bhumla Preeti P Jain Manjari M Bhattacharya Saswata S

Scientific reports 20221220 1

Topological Insulators (TIs) are unique materials where insulating bulk hosts linearly dispersing surface states protected by the Time-Reversal Symmetry. These states lead to dissipationless current flow, which makes this class of materials highly promising for spintronic applications. Here, we predict TIs by employing state-of-the-art first-principles based methodologies, viz., density functional theory and many-body perturbation theory (G[Formula: see text]W[Formula: see text]) combined with s ...[more]

PMID: 36539475

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Dataset Information

Exploring strong and weak topological states on isostructural substitutions in TlBiSe[Formula: see text].

Publications

Exploring strong and weak topological states on isostructural substitutions in TlBiSe[Formula: see text].

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