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Ultrafast Optical Microscopy of Single Monolayer Molybdenum Disulfide Flakes.

ABSTRACT: We have performed ultrafast optical microscopy on single flakes of atomically thin CVD-grown molybdenum disulfide, using non-degenerate femtosecond pump-probe spectroscopy to excite and probe carriers above and below the indirect and direct band gaps. These measurements reveal the influence of layer thickness on carrier dynamics when probing near the band gap. Furthermore, fluence-dependent measurements indicate that carrier relaxation is primarily influenced by surface-related defect and trap states after above-bandgap photoexcitation. The ability to probe femtosecond carrier dynamics in individual flakes can thus give much insight into light-matter interactions in these two-dimensional nanosystems.

SUBMITTER: Seo M

PROVIDER: S-EPMC4753495 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

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Ultrafast Optical Microscopy of Single Monolayer Molybdenum Disulfide Flakes.

Seo Minah M Yamaguchi Hisato H Mohite Aditya D AD Boubanga-Tombet Stephane S Blancon Jean-Christophe JC Najmaei Sina S Ajayan Pulickel M PM Lou Jun J Taylor Antoinette J AJ Prasankumar Rohit P RP

Scientific reports 20160215

We have performed ultrafast optical microscopy on single flakes of atomically thin CVD-grown molybdenum disulfide, using non-degenerate femtosecond pump-probe spectroscopy to excite and probe carriers above and below the indirect and direct band gaps. These measurements reveal the influence of layer thickness on carrier dynamics when probing near the band gap. Furthermore, fluence-dependent measurements indicate that carrier relaxation is primarily influenced by surface-related defect and trap s ...[more]

PMID: 26876194

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