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Tuning the bandgap of exfoliated InSe nanosheets by quantum confinement.

ABSTRACT: Strong quantization effects and tuneable near-infrared photoluminescence emission are reported in mechanically exfoliated crystals of γ-rhombohedral semiconducting InSe. The optical properties of InSe nanosheets differ qualitatively from those reported recently for exfoliated transition metal dichalcogenides and indicate a crossover from a direct to an indirect band gap semiconductor when the InSe flake thickness is reduced to a few nanometers.

SUBMITTER: Mudd GW

PROVIDER: S-EPMC4065344 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature

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Tuning the bandgap of exfoliated InSe nanosheets by quantum confinement.

Mudd Garry W GW Svatek Simon A SA Ren Tianhang T Patanè Amalia A Makarovsky Oleg O Eaves Laurence L Beton Peter H PH Kovalyuk Zakhar D ZD Lashkarev George V GV Kudrynskyi Zakhar R ZR Dmitriev Alexandr I AI

Advanced materials (Deerfield Beach, Fla.) 20130821 40

Strong quantization effects and tuneable near-infrared photoluminescence emission are reported in mechanically exfoliated crystals of γ-rhombohedral semiconducting InSe. The optical properties of InSe nanosheets differ qualitatively from those reported recently for exfoliated transition metal dichalcogenides and indicate a crossover from a direct to an indirect band gap semiconductor when the InSe flake thickness is reduced to a few nanometers. ...[more]

PMID: 23966225

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