title: Study of exciton transfer in dense quantum dot nanocomposites.
abstract: Nanocomposites of colloidal quantum dots (QDs) integrated into conjugated polymers (CPs) are key to hybrid optoelectronics, where engineering the excitonic interactions at the nanoscale is crucial. For such excitonic operation, it was believed that exciton diffusion is essential to realize nonradiative energy transfer from CPs to QDs. In this study, contrary to the previous literature, efficient exciton transfer is demonstrated in the nanocomposites of dense QDs, where exciton transfer can be as efficient as 80% without requiring the assistance of exciton diffusion. This is enabled by uniform dispersion of QDs at high density (up to ∼70 wt%) in the nanocomposite while avoiding phase segregation. Theoretical modeling supports the experimental observation of weakly temperature dependent nonradiative energy transfer dynamics. This new finding provides the ability to design hybrid light-emitting diodes that show an order of magnitude enhanced external quantum efficiencies.
authors.affiliation: Department of Electrical and Electronics Engineering, Department of Physics, Department of Chemistry, and UNAM-National Nanotechnology Research Center, Institute of Materials Science and Nanotechnology, Bilkent University, Ankara, TR-06800, Turkey. volkan@bilkent.edu.tr hvdemir@ntu.edu.sg.
authors.forename: Burak
authors.initials: B
authors.lastname: Guzelturk
authors.forename: Pedro Ludwig
authors.initials: PL
authors.lastname: Hernandez-Martinez
authors.forename: Vijay Kumar
authors.initials: VK
authors.lastname: Sharma
authors.forename: Yasemin
authors.initials: Y
authors.lastname: Coskun
authors.forename: Vusala
authors.initials: V
authors.lastname: Ibrahimova
authors.forename: Donus
authors.initials: D
authors.lastname: Tuncel
authors.forename: Alexander O
authors.initials: AO
authors.lastname: Govorov
authors.forename: Xiao Wei
authors.initials: XW
authors.lastname: Sun
authors.forename: Qihua
authors.initials: Q
authors.lastname: Xiong
authors.forename: Hilmi Volkan
authors.initials: HV
authors.lastname: Demir