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dc.contributor.advisorLi, Xiaosongen_US
dc.contributor.authorMay, Joseph Williamen_US
dc.date.accessioned2014-10-13T20:01:38Z
dc.date.available2014-10-13T20:01:38Z
dc.date.submitted2014en_US
dc.identifier.otherMay_washington_0250E_12971.pdfen_US
dc.identifier.urihttp://hdl.handle.net/1773/26406
dc.descriptionThesis (Ph.D.)--University of Washington, 2014en_US
dc.description.abstractThe ability to tune the electronic, magnetic, and optical properties of II-VI semiconductor quantum dots (QDs) makes these materials ideal candidates in the fabrication of new solar energy, spin electronic, and phosphorescent devices. This dissertation makes use of electronic structure theory to provide insight into the physical underpinnings of magnetic exchange and photoexcitation in Mn<super>2+</super>- and Co<super>2+</super>-doped CdSe and ZnO QDs. Specifically, new methods for controlling these physical effects via the incorporation of various dopants or changes in the QD's size and shape are presented. Several examples of these control techniques are discussed in this dissertation. Ferromagnetic alignment of multiple unpaired Mn<super>2+</super> 3<italic>d</italic> electrons is predicted when the p-type defect N<super>2-</super> is present in ZnO QDs. Control over the magnetic exchange interactions between charge carriers and TM<super>2+</super> dopants that give rise to ferromagnetism is achieved by distorting the QD's shape along one or two dimensions. Aliovalent doping with Al<super>3+</super> produces QDs that are spectroscopically identical to photochemically charged QDs, yet exhibit different reactivities. A unique temperature dependence of the luminescence and photoconductivity in large Co<super>2+</super>-doped ZnO QDs is predicted upon excitation of its mid-gap excited state. Lastly, a new method for the optimization of transition state molecular geometries is shown to exhibit fast optimization and to be advantageous for difficult optimizations where the reaction path is flat, ideal for optimizing large QD structures.en_US
dc.format.mimetypeapplication/pdfen_US
dc.language.isoen_USen_US
dc.rightsCopyright is held by the individual authors.en_US
dc.subjectcharge transfer; density functional theory; dilute magnetic semiconductor; electronic structure; magnetic exchange; quantum doten_US
dc.subject.otherChemistryen_US
dc.subject.otherMaterials Scienceen_US
dc.subject.otherchemistryen_US
dc.titleTheoretical Insight into the Manipulation of the Optical and Magnetic Properties of Transition-Metal-doped II-VI Semiconductor Quantum Dotsen_US
dc.typeThesisen_US
dc.embargo.termsOpen Accessen_US


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