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Controlling Topological States in Topological/Normal Insulator Heterostructures.

ABSTRACT: We have performed a systematic investigation of the nature of the nontrivial interface states in topological/normal insulator (TI/NI) heterostructures. On the basis of first principles and a recently developed scheme to construct ab initio effective Hamiltonian matrices from density functional theory calculations, we studied systems of realistic sizes with high accuracy and control over the relevant parameters such as TI and NI band alignment, NI gap, and spin-orbit coupling strength. Our results for IV-VI compounds show the interface gap tunability by appropriately controlling the NI thickness, which can be explored for device design. Also, we verified the preservation of an in-plane spin texture in the interface-gaped topological states.

SUBMITTER: Costa M

PROVIDER: S-EPMC6643377 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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Controlling Topological States in Topological/Normal Insulator Heterostructures.

Costa Marcio M Costa Antônio T AT Freitas Walter A WA Schmidt Tome M TM Buongiorno Nardelli Marco M Fazzio Adalberto A

ACS omega 20181126 11

We have performed a systematic investigation of the nature of the nontrivial interface states in topological/normal insulator (TI/NI) heterostructures. On the basis of first principles and a recently developed scheme to construct ab initio effective Hamiltonian matrices from density functional theory calculations, we studied systems of realistic sizes with high accuracy and control over the relevant parameters such as TI and NI band alignment, NI gap, and spin-orbit coupling strength. Our result ...[more]

PMID: 31458234

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