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Topological phase transition between a normal insulator and a topological metal state in a quasi-one-dimensional system.

ABSTRACT: We theoretically report the finding of a new kind of topological phase transition between a normal insulator and a topological metal state where the closing-reopening of bandgap is accompanied by passing the Fermi level through an additional band. The resulting nontrivial topological metal phase is characterized by stable zero-energy localized edge states that exist within the full gapless bulk states. Such states living on a quasi-one-dimensional system with three sublattices per unit cell are protected by hidden inversion symmetry. While other required symmetries such as chiral, particle-hole, or full inversion symmetry are absent in the system.

SUBMITTER: Jangjan M

PROVIDER: S-EPMC8217258 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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Topological phase transition between a normal insulator and a topological metal state in a quasi-one-dimensional system.

Jangjan Milad M Hosseini Mir Vahid MV

Scientific reports 20210621 1

We theoretically report the finding of a new kind of topological phase transition between a normal insulator and a topological metal state where the closing-reopening of bandgap is accompanied by passing the Fermi level through an additional band. The resulting nontrivial topological metal phase is characterized by stable zero-energy localized edge states that exist within the full gapless bulk states. Such states living on a quasi-one-dimensional system with three sublattices per unit cell are ...[more]

PMID: 34155297

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