Exciton harvesting systems of nanocrystals

Simple item page
buir.advisorDemir, Hilmi Volkan
dc.contributor.authorMutlugün, Evren
dc.date.accessioned2016-01-08T18:24:21Z
dc.date.available2016-01-08T18:24:21Z
dc.date.issued2011
dc.departmentDepartment of Physicsen_US
dc.descriptionAnkara : The Department of Physics and the Institute of Engineering and Sciences of Bilkent University, 2011.en_US
dc.descriptionThesis (Ph. D.) -- Bilkent University, 2011.en_US
dc.descriptionIncludes bibliographical references leaves 123-143.en_US
dc.description.abstractSemiconductor nanocrystals, also known as colloidal quantum dots, have gained substantial scientific interest for innovative light harvesting applications including those in biolabeling. Organic dyes and fluorescent proteins are widely used in biotargeting and live cell imaging, but their intrinsic optical properties, such as narrow excitation windows, limit their potential for advanced applications, e.g., spectral multiplexing. Compared to these organic fluorophores, favorable properties of the quantum dots including high photoluminescence quantum yields together with tunable emission peaks and narrow spectral emission widths, high extinction coefficients, and broad absorption bands enable us to discover and innovate light harvesting composites. In such systems, however, the scientific challenge is to achieve high levels of energy transfer from one species to the other, with additional features of versatility and tunability. To address these problems, as a conceptual advancement, this thesis proposes and demonstrates a new class of versatile light harvesting systems of semiconductor nanocrystals mediated by excitonic interactions based on Förstertype nonradiative energy transfer. In this thesis, we synthesized near-unity efficiency colloidal quantum dots with as-synthesized photoluminescence quantum yields of >95%. As proof-of-concept demonstrations, we studied and achieved highly efficient exciton harvesting systems of quantum dots bound to fluorescent proteins, where the excitons are zipped from the dots to the proteins in the composite. This led to many folds of light harvesting (tunable up to 15 times) in the case of the green fluorescent protein. Using organic dye molecules electrostatically interacting with quantum dots, we showed high levels of exciton migration from the dots to the molecules (up to 94%). Furthermore, we demonstrated stand-alone, flexible membranes of nanocrystals in unprecedentedly large areas (> 50 cm × 50 cm), which paves the way for highend, large-scale applications. In the thesis, we also developed exciton-exciton coupling models to support the experimental results. This thesis opens up new possibilities for exciton-harvesting in biolabeling and optoelectronics.en_US
dc.description.degreePh.D.en_US
dc.description.statementofresponsibilityMutlugün, Evrenen_US
dc.format.extentxx, 151 leaves, illustrations, graphsen_US
dc.identifier.urihttp://hdl.handle.net/11693/15770
dc.language.isoEnglishen_US
dc.publisherBilkent Universityen_US
dc.rightsinfo:eu-repo/semantics/openAccessen_US
dc.subjectSemiconductor nanocrystalsen_US
dc.subjectnonradiative energy transferen_US
dc.subjectexcitonsen_US
dc.subjectlight harvestingen_US
dc.subject.lccQC611.6.Q35 M881 2011en_US
dc.subject.lcshSemiconductors--Optical properties.en_US
dc.subject.lcshQuantum dots.en_US
dc.subject.lcshNanocrystals.en_US
dc.subject.lcshEnergy transfer.en_US
dc.subject.lcshExciton theory.en_US
dc.titleExciton harvesting systems of nanocrystalsen_US
dc.typeThesisen_US

Files

Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
0006477.pdf
Size:
8.58 MB
Format:
Adobe Portable Document Format
Download

Collections

Dept. of Physics - Ph.D. / Sc.D.