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Two Dimensional β-InSe with Layer-Dependent Properties: Band Alignment, Work Function and Optical Properties.

ABSTRACT: Density functional theory calculations of the layer (L)-dependent electronic band structure, work function and optical properties of β-InSe have been reported. Owing to the quantum size effects (QSEs) in β-InSe, the band structures exhibit direct-to-indirect transitions from bulk β-InSe to few-layer β-InSe. The work functions decrease monotonically from 5.22 eV (1 L) to 5.0 eV (6 L) and then remain constant at 4.99 eV for 7 L and 8 L and drop down to 4.77 eV (bulk β-InSe). For optical properties, the imaginary part of the dielectric function has a strong dependence on the thickness variation. Layer control in two-dimensional layered materials provides an effective strategy to modulate the layer-dependent properties which have potential applications in the next-generation high performance electronic and optoelectronic devices.

SUBMITTER: Sang DK

PROVIDER: S-EPMC6358860 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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Two Dimensional β-InSe with Layer-Dependent Properties: Band Alignment, Work Function and Optical Properties.

Sang David K DK Wang Huide H Qiu Meng M Cao Rui R Guo Zhinan Z Zhao Jinlai J Li Yu Y Xiao Quanlan Q Fan Dianyuan D Zhang Han H

Nanomaterials (Basel, Switzerland) 20190109 1

Density functional theory calculations of the layer (L)-dependent electronic band structure, work function and optical properties of β-InSe have been reported. Owing to the quantum size effects (QSEs) in β-InSe, the band structures exhibit direct-to-indirect transitions from bulk β-InSe to few-layer β-InSe. The work functions decrease monotonically from 5.22 eV (1 L) to 5.0 eV (6 L) and then remain constant at 4.99 eV for 7 L and 8 L and drop down to 4.77 eV (bulk β-InSe). For optical properties ...[more]

PMID: 30634415

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