title: Phonon-assisted exciton transfer into silicon using nanoemitters: the role of phonons and temperature effects in Förster resonance energy transfer.
abstract: We study phonon-assisted Förster resonance energy transfer (FRET) into an indirect band-gap semiconductor using nanoemitters. The unusual temperature dependence of this energy transfer, which is measured using the donor nanoemitters of quantum dot (QD) layers integrated on the acceptor monocrystalline bulk silicon as a model system, is predicted by a phonon-assisted exciton transfer model proposed here. The model includes the phonon-mediated optical properties of silicon, while considering the contribution from the multimonolayer-equivalent QD film to the nonradiative energy transfer, which is derived with a d(-3) distance dependence. The FRET efficiencies are experimentally observed to decrease at cryogenic temperatures, which are well explained by the model considering the phonon depopulation in the indirect band-gap acceptor together with the changes in the quantum yield of the donor. These understandings will be crucial for designing FRET-enabled sensitization of silicon based high-efficiency excitonic systems using nanoemitters.
authors.affiliation: Department of Physics and Department of Electrical and Electronics Engineering, UNAM-Institute of Materials Science and Nanotechnology, Bilkent University , Ankara 06800, Turkey.
authors.forename: Aydan
authors.initials: A
authors.lastname: Yeltik
authors.forename: Burak
authors.initials: B
authors.lastname: Guzelturk
authors.forename: Pedro Ludwig
authors.initials: PL
authors.lastname: Hernandez-Martinez
authors.forename: Alexander O
authors.initials: AO
authors.lastname: Govorov
authors.forename: Hilmi Volkan
authors.initials: HV
authors.lastname: Demir