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arXiv · 1506.04716

Electrical control of near-field energy transfer between quantum dots and 2D semiconductors

Dhiraj Prasai·Andrey R. Klots·A. K. M. Newaz·J. Scott Niezgoda·Noah J. Orfield·Carlos A. Escobar·Alex Wynn·Anatoly Efimov·G. Kane Jennings·Sandra J. Rosenthal·Kirill I. Bolotin
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Abstract

We investigate near-field energy transfer between chemically synthesized quantum dots (QDs) and two-dimensional semiconductors. We fabricate devices in which electrostatically gated semiconducting monolayer molybdenum disulfide (MoS2) is placed atop a homogenous self-assembled layer of core-shell CdSSe QDs. We demonstrate efficient non-radiative F\"orster resonant energy transfer (FRET) from QDs into MoS2 and prove that modest gate-induced variation in the excitonic absorption of MoS2 lead to large (~500%) changes in the FRET rate. This, in turn, allows for up to ~75% electrical modulation of QD photoluminescence intensity. The hybrid QD/MoS2 devices operate within a small voltage range, allow for continuous modification of the QD photoluminescence intensity, and can be used for selective tuning of QDs emitting in the visible-IR range.

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Dhiraj Prasai, Andrey R. Klots, A. K. M. Newaz, J. Scott Niezgoda, Noah J. Orfield, Carlos A. Escobar, Alex Wynn, Anatoly Efimov, G. Kane Jennings, Sandra J. Rosenthal, Kirill I. Bolotin. 2015-06-15. Electrical control of near-field energy transfer between quantum dots and 2D semiconductors. https://doi.org/10.1021/acs.nanolett.5b00514

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