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Strain-Induced Spatial and Spectral Isolation of Quantum Emitters in Mono- and Bilayer WSe2.

ABSTRACT: Two-dimensional transition metal dichalcogenide semiconductors are intriguing hosts for quantum light sources due to their unique optoelectronic properties. Here, we report that strain gradients, either unintentionally induced or generated by substrate patterning, result in spatially and spectrally isolated quantum emitters in mono- and bilayer WSe2. By correlating localized excitons with localized strain variations, we show that the quantum emitter emission energy can be red-tuned up to a remarkable ?170 meV. We probe the fine-structure, magneto-optics, and second-order coherence of a strained emitter. These results raise the prospect of strain-engineering quantum emitter properties and deterministically creating arrays of quantum emitters in two-dimensional semiconductors.

SUBMITTER: Kumar S

PROVIDER: S-EPMC4643357 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature

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Strain-Induced Spatial and Spectral Isolation of Quantum Emitters in Mono- and Bilayer WSe2.

Kumar S S Kaczmarczyk A A Gerardot B D BD

Nano letters 20151026 11

Two-dimensional transition metal dichalcogenide semiconductors are intriguing hosts for quantum light sources due to their unique optoelectronic properties. Here, we report that strain gradients, either unintentionally induced or generated by substrate patterning, result in spatially and spectrally isolated quantum emitters in mono- and bilayer WSe2. By correlating localized excitons with localized strain variations, we show that the quantum emitter emission energy can be red-tuned up to a remar ...[more]

PMID: 26480237

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