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arXiv · 1610.03026

Direct Patterning of Colloidal Quantum-Dot Thin Films for Enhanced and Spectrally Selective Out-Coupling of Emission

Ferry Prins·David K. Kim·Jian Cui·Eva De Leo·Kevin M. McPeak·David J. Norris
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Abstract

We report on a template-stripping method for the direct surface patterning of colloidal quantum-dot thin films to produce highly luminescent structures with feature sizes less than 100 nm. Through the careful design of high quality bulls-eye gratings we can produce strong directional beaming (10{\deg} divergence) with up to six-fold out-coupling enhancement of spontaneous emission in the surface-normal direction. A transition to narrow single-mode lasing is observed in these same structures at thresholds as low as 120 {\mu}J/cm2. Furthermore, making use of the size-tunable character of colloidal quantum dots, we demonstrate spectrally selective out-coupling of light from mixed quantum-dot films. Our results provide a straightforward route towards significantly improved optical properties of colloidal quantum-dot assemblies.

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Ferry Prins, David K. Kim, Jian Cui, Eva De Leo, Kevin M. McPeak, David J. Norris. 2016-10-10. Direct Patterning of Colloidal Quantum-Dot Thin Films for Enhanced and Spectrally Selective Out-Coupling of Emission. https://doi.org/10.1021/acs.nanolett.6b03212

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