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DOE OSTI · 1782081

Site-Controlled Quantum Emitters in Monolayer MoSe 2

Yu, Leo·Deng, Minda·Zhang, Jingyuan Linda·Borghardt, Sven·Kardynal, Beata·Vučković, Jelena·Heinz, Tony F.
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Abstract

Atomically thin semiconductors provide a highly attractive platform for quantum emitters (QEs): They can be combined with arbitrary substrates, can be spatially aligned with photonic structures, and can be electrically driven. All QEs reported to date in these materials have, however, relied on nominally spin-forbidden transitions, with radiative rates falling substantially below those of other solid-state QE systems. In this work, we employ strain confinement in monolayer MoSe 2 to produce engineered QEs, as confirmed in photon antibunching measurements. We discuss spin-allowed versus spin-forbidden transitions based on magneto- and time-resolved photoluminescence measurements. We calculate a radiative rate for spin-allowed quantum emission greater than 1 ns –1 , which exceeds reported radiative rates of WSe 2 QEs by 2 orders of magnitude.

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2D materials77 NANOSCIENCE AND NANOTECHNOLOGYdepositionexcitonsmagnetic propertiesmolybdenum diselenide monolayersmonolayersquantum confinementquantum emitterssingle photon emittersstrain engineering

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Yu, Leo, Deng, Minda, Zhang, Jingyuan Linda, Borghardt, Sven, Kardynal, Beata, Vučković, Jelena, Heinz, Tony F.. 2021-03-10. Site-Controlled Quantum Emitters in Monolayer MoSe 2. https://doi.org/10.1021/acs.nanolett.0c04282

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