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Suppressed topological phase transitions due to nonsymmorphism in SnTe stacking.

ABSTRACT: We combine first principles calculations with a group theory analysis to investigate topological phase transitions in the stacking of SnTe monolayers. We show that distinct finite stacking yields different symmetry-imposed degeneracy, which dictates the hybridization properties of opposite surface states. For SnTe aligned along the [001] direction, an (even) odd number of monolayers yields a (non)symmorphic space group. For the symmorphic case, the hybridization of surface states lead to band inversions and topological phase transitions as the sample height is reduced. In contrast, for a nonsymmorphic stacking, an extra degeneracy is guaranteed by symmetry, thus avoiding the hybridization and topological phase transitions, even in the limit of a few monolayers. Our group theory analysis provide a clear picture for this phenomenology and matches well the first principles calculations.

SUBMITTER: Araujo AL

PROVIDER: S-EPMC6013480 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Suppressed topological phase transitions due to nonsymmorphism in SnTe stacking.

Araújo Augusto L AL Ferreira Gerson J GJ Schmidt Tome M TM

Scientific reports 20180621 1

We combine first principles calculations with a group theory analysis to investigate topological phase transitions in the stacking of SnTe monolayers. We show that distinct finite stacking yields different symmetry-imposed degeneracy, which dictates the hybridization properties of opposite surface states. For SnTe aligned along the [001] direction, an (even) odd number of monolayers yields a (non)symmorphic space group. For the symmorphic case, the hybridization of surface states lead to band in ...[more]

PMID: 29930356

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