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Tunability Limit of Photoluminescence in Colloidal Silicon Nanocrystals.

ABSTRACT: Luminescent silicon nanocrystals (Si NCs) have attracted tremendous research interest. Their size dependent photoluminescence (PL) shows great promise in various optoelectronic and biomedical applications and devices. However, it remains unclear why the exciton emission is limited to energy below 2.1?eV, no matter how small the nanocrystal is. Here we interpret a nanosecond transient yellow emission band at 590?nm (2.1?eV) as a critical limit of the wavelength tunability in colloidal silicon nanocrystals. In the "large size" regime (d?>?~3?nm), quantum confinement dominantly determines the PL wavelength and thus the PL peak blue shifts upon decreasing the Si NC size. In the "small size" regime (d?

SUBMITTER: Wen X

PROVIDER: S-EPMC4510486 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

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Tunability Limit of Photoluminescence in Colloidal Silicon Nanocrystals.

Wen Xiaoming X Zhang Pengfei P Smith Trevor A TA Anthony Rebecca J RJ Kortshagen Uwe R UR Yu Pyng P Feng Yu Y Shrestha Santosh S Coniber Gavin G Huang Shujuan S

Scientific reports 20150722

Luminescent silicon nanocrystals (Si NCs) have attracted tremendous research interest. Their size dependent photoluminescence (PL) shows great promise in various optoelectronic and biomedical applications and devices. However, it remains unclear why the exciton emission is limited to energy below 2.1 eV, no matter how small the nanocrystal is. Here we interpret a nanosecond transient yellow emission band at 590 nm (2.1 eV) as a critical limit of the wavelength tunability in colloidal silicon nan ...[more]

PMID: 26198209

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