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dc.creatorPark, Keeseong, 1972-en_US
dc.date.accessioned2008-08-28T23:36:15Z
dc.date.available2008-08-28T23:36:15Z
dc.date.created2007en_US
dc.date.issued2008-08-28T23:36:15Z
dc.identifierb68890060en_US
dc.identifier.urihttp://hdl.handle.net/2152/3242
dc.descriptiontext
dc.description.abstractOxygen hole-doping effects on a spin-chain system, Ca[subscript 2+chi]Y[2-chi]Cu₅O[subscript 10-delta](CaYCuO) are reported. CaYCuO is a good specimen to study the magnetic properties of the CuO₂ chain at the ground state because it has no complex structure other than the chain and it has hole dopability up to the formal copper valence number of +2.4. Specifically, we can dope holes into the CuO₂ chain by substituting Ca²⁺ for Y³⁺ or by utilizing oxygen deficiency. After a systematic study of the two methods to dope holes, we found that oxygen doping makes a more critical change in magnetic ordering in the chain than the replacement of Ca²⁺. Oxygen deficiency effects of the chain on the magnetic properties were explained using a mean field theory. A new relation for the effective hole doping was found as p = x - [alpha delta], where a = 3/2(x - [delta]) - 1/4. We study the anisotropy of magnetic properties of single crystal Li-cathode material (LiFePO₄) for g-factor, Curie-Weiss temperature, and effective moment. Magnetic properties Au/SiO₂ coated [gamma]-Fe₂O₃ are compared with pure [gamma]-Fe₂O₃ finding a decrease in the blocking temperature and the irreversible temperature for the coated nanoparticles.en_US
dc.format.mediumelectronicen_US
dc.language.isoengen_US
dc.rightsCopyright is held by the author. Presentation of this material on the Libraries' web site by University Libraries, The University of Texas at Austin was made possible under a limited license grant from the author who has retained all copyrights in the works.en_US
dc.subject.lcshOxygen--Industrial applicationsen_US
dc.subject.lcshCopper oxide superconductorsen_US
dc.subject.lcshMinerals--Magnetic propertiesen_US
dc.titleMagnetic phase diagram of Ca₂₊xY₂₋xCu₅O₁₀₋[delta]: oxygen hole-doping effectsen_US
dc.description.departmentPhysicsen_US
dc.identifier.oclc174113855en_US
dc.type.genreThesisen_US
thesis.degree.departmentPhysicsen_US
thesis.degree.disciplinePhysicsen_US
thesis.degree.grantorThe University of Texas at Austinen_US
thesis.degree.levelDoctoralen_US
thesis.degree.nameDoctor of Philosophyen_US


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