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Realization of tunable Dirac cone and insulating bulk states in topological insulators (Bi(1-x)Sb(x))(2)Te(3).

ABSTRACT: The bulk-insulating topological insulators with tunable surface states are necessary for applications in spintronics and quantum computation. Here we present theoretical evidence for modulating the topological surface states and achieving the insulating bulk states in solid-solution (Bi(1-x)Sb(x))(2)Te(3). Our results reveal that the band inversion occurs in (Bi(1-x)Sb(x))(2)Te(3), indicating the non-triviality across the entire composition range, and the Dirac point moves upwards till it lies within the bulk energy gap accompanying the increase of Sb concentration x. In addition, with increasing x, the formation of prominent native defects becomes much more difficult, resulting in the truly insulating bulk. The solid-solution system is a promising way of tuning the properties of topological insulators and designing novel topologically insulating devices.

SUBMITTER: Niu C

PROVIDER: S-EPMC3521154 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Realization of tunable Dirac cone and insulating bulk states in topological insulators (Bi(1-x)Sb(x))(2)Te(3).

Niu Chengwang C Dai Ying Y Zhu Yingtao Y Ma Yandong Y Yu Lin L Han Shenghao S Huang Baibiao B

Scientific reports 20121213

The bulk-insulating topological insulators with tunable surface states are necessary for applications in spintronics and quantum computation. Here we present theoretical evidence for modulating the topological surface states and achieving the insulating bulk states in solid-solution (Bi(1-x)Sb(x))(2)Te(3). Our results reveal that the band inversion occurs in (Bi(1-x)Sb(x))(2)Te(3), indicating the non-triviality across the entire composition range, and the Dirac point moves upwards till it lies w ...[more]

PMID: 23240080

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