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Large-area and bright pulsed electroluminescence in monolayer semiconductors.

ABSTRACT: Transition-metal dichalcogenide monolayers have naturally terminated surfaces and can exhibit a near-unity photoluminescence quantum yield in the presence of suitable defect passivation. To date, steady-state monolayer light-emitting devices suffer from Schottky contacts or require complex heterostructures. We demonstrate a transient-mode electroluminescent device based on transition-metal dichalcogenide monolayers (MoS2, WS2, MoSe2, and WSe2) to overcome these problems. Electroluminescence from this dopant-free two-terminal device is obtained by applying an AC voltage between the gate and the semiconductor. Notably, the electroluminescence intensity is weakly dependent on the Schottky barrier height or polarity of the contact. We fabricate a monolayer seven-segment display and achieve the first transparent and bright millimeter-scale light-emitting monolayer semiconductor device.

SUBMITTER: Lien DH

PROVIDER: S-EPMC5955902 | biostudies-other | 2018 Mar

REPOSITORIES: biostudies-other

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Large-area and bright pulsed electroluminescence in monolayer semiconductors.

Lien Der-Hsien DH Amani Matin M Desai Sujay B SB Ahn Geun Ho GH Han Kevin K He Jr-Hau JH Ager Joel W JW Wu Ming C MC Javey Ali A

Nature communications 20180326 1

Transition-metal dichalcogenide monolayers have naturally terminated surfaces and can exhibit a near-unity photoluminescence quantum yield in the presence of suitable defect passivation. To date, steady-state monolayer light-emitting devices suffer from Schottky contacts or require complex heterostructures. We demonstrate a transient-mode electroluminescent device based on transition-metal dichalcogenide monolayers (MoS2, WS2, MoSe2, and WSe2) to overc ...[more]

PMID: 29581419

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