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dc.contributor.advisorDemir, Hilmi Volkan
dc.contributor.authorAkın, Onur
dc.date.accessioned2016-01-08T18:19:04Z
dc.date.available2016-01-08T18:19:04Z
dc.date.issued2010
dc.identifier.urihttp://hdl.handle.net/11693/15471
dc.descriptionAnkara : The Department of Electrical and Electronics Engineering and the Institute of Engineering and Sciences of Bilkent University, 2010.en_US
dc.descriptionThesis (Master's) -- Bilkent University, 2010.en_US
dc.descriptionIncludes bibliographical references leaves 57-60.en_US
dc.description.abstractNonradiative energy transfer finds important applications in nanophotonics and nanobiotechnology including nanoscale optical waveguiding and biological nanosensors. Various fluorophores can take part in such energy transfer interactions in close proximity of each other. Their emission kinetics can be strongly modified and controlled as a result. For example, colloidal semiconductor quantum dots, also known as nanocrystals, have widely been shown to serve as donors and acceptors among themselves or with other fluorescent species to transfer excitation energy nonradiatively. In their close proximity, emission characteristics of such fluorophores can also be altered when coupled with plasmonic structures, e.g., metal nanoparticles. One favored result of these plasmon-exciton interactions is the emission enhancement. In principle it is possible to plasmon-couple acceptor-donor pairs of nonradiative energy transfer to modify their transfer rate. Such plasmon-mediated energy transfer has been demonstrated, where both acceptor-donor pairs are plasmoncoupled. In these cases, however, the resulting plasmon-exciton interactions are not controlled to take place either at the donor site or the acceptor site but at both of the sites. Therefore, it has previously not been possible to identify the coupled interactions. In this thesis, we propose and demonstrate cascaded plasmonic - nonradiative energy transfer interactions that are controlled by selectively plasmon-coupling either only the donor quantum dots or only the acceptor quantum dots. For that, we designed a novel self-assembly architecture of our hybrid layered systems of semiconductor nanocrystals and metal nanoparticles in a bottom-up fashion through precise spatial and spectral control. This scheme uniquely allowed for the ability to spatially control plasmonexciton interactions to take place either at the “start” site (donors) or “finish” site (acceptors) of the energy transfer. This control was achieved by placing the plasmonic layer in the right proximity of the donors (for strong donor-exciton plasmon-coupling) while sufficiently being far away from the acceptors (for weak acceptor-exciton plasmon-coupling), or vice versa. Here we comparatively studied and analyzed consequent modifications of quantum dot emission kinetics in response to both cases of plasmon-coupling to only the donors and to only the acceptors through steady-state and time-resolved photoluminescence measurements, along with their lifetime and rate calculations. Such cascaded energy transfer interactions in the strong exciton-plasmon coupling region hold great promise for innovative near-field photonic devices and biological tags. system.en_US
dc.description.statementofresponsibilityAkın, Onuren_US
dc.format.extentxvi, 60 leaves, illustrationsen_US
dc.language.isoEnglishen_US
dc.rightsinfo:eu-repo/semantics/openAccessen_US
dc.subjectFörster-type non-radiative energy transferen_US
dc.subjectplasmonicsen_US
dc.subjectlocalized surface plasmonsen_US
dc.subjectsemiconductor nanocrystalsen_US
dc.subjectcolloidal quantum dotsen_US
dc.subjectgold nanoparticlesen_US
dc.subjectmetal nanostructuresen_US
dc.subjectexcitonsen_US
dc.subjectspontaneous emissionen_US
dc.subjectphotoluminescenceen_US
dc.subjectplasmon coupled photoluminescenceen_US
dc.subject.lccQC611.6.Q35 A55 2010en_US
dc.subject.lcshSemiconductors.en_US
dc.subject.lcshQuantum dots.en_US
dc.subject.lcshPlasmons (Physics)en_US
dc.subject.lcshNanostructures.en_US
dc.subject.lcshNanocrystals.en_US
dc.subject.lcshEnergy transfer.en_US
dc.titleCascading and modifying nonradiative energy transfer mechanisms in strong coupling region of plasmons and excitons in semiconductor quantum dotsen_US
dc.typeThesisen_US
dc.departmentDepartment of Electrical and Electronics Engineeringen_US
dc.publisherBilkent Universityen_US
dc.description.degreeM.S.en_US


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