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Prediction of Quantum Anomalous Hall Insulator in half-fluorinated GaBi Honeycomb.

ABSTRACT: Using first-principles electronic structure calculations, we predict half-fluorinated GaBi honeycomb under tensile strain to harbor a quantum anomalous Hall (QAH) insulator phase. We show that this QAH phase is driven by a single inversion in the band structure at the ? point. Moreover, we have computed the electronic spectrum of a half-fluorinated GaBi nanoribbon with zigzag edges, which shows that only one edge band crosses the Fermi level within the band gap. Our results suggest that half-fluorination of the GaBi honeycomb under tensile strain could provide a new platform for developing novel spintronics devices based on the QAH effect.

SUBMITTER: Chen SP

PROVIDER: S-EPMC4979090 | biostudies-other | 2016

REPOSITORIES: biostudies-other

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Prediction of Quantum Anomalous Hall Insulator in half-fluorinated GaBi Honeycomb.

Chen Sung-Ping SP Huang Zhi-Quan ZQ Crisostomo Christian P CP Hsu Chia-Hsiu CH Chuang Feng-Chuan FC Lin Hsin H Bansil Arun A

Scientific reports 20160810

Using first-principles electronic structure calculations, we predict half-fluorinated GaBi honeycomb under tensile strain to harbor a quantum anomalous Hall (QAH) insulator phase. We show that this QAH phase is driven by a single inversion in the band structure at the Γ point. Moreover, we have computed the electronic spectrum of a half-fluorinated GaBi nanoribbon with zigzag edges, which shows that only one edge band crosses the Fermi level within the band gap. Our results suggest that half-flu ...[more]

PMID: 27507248

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