Investigation of electronic transport and magnetic properties in Ca₂-₂xLa₂xRu₂-xCoxO₆
dc.contributor.advisor | Goodenough, John B. | |
dc.creator | Kim, Sangwon, 1978- | |
dc.date.accessioned | 2017-03-28T16:05:06Z | |
dc.date.accessioned | 2018-01-22T22:31:52Z | |
dc.date.available | 2017-03-28T16:05:06Z | |
dc.date.available | 2018-01-22T22:31:52Z | |
dc.date.issued | 2007-08 | |
dc.description.abstract | Ca2-2xLa2xRu2-xCoxO6 ( 0.0 ≤ x ≤ 1.0 ) is prepared by a "Polymerizable-Complex Method." Electronic transport and magnetic properties are measured to show that the system becomes semiconducting at x ≈ 0.1 and goes through long-range antiferromagnetic ordering at x ≈ 0.4. The proximity in Néel temperature TN of La2RuCoO6 to that of La2TiCoO6 previously reported suggests that the magnetic moment of Ru4+ becomes quenched as temperature decreases. This suppression is explained by a theory that due to (1) the strong spin-orbit coupling ( large spin-orbit coupling constant [Greek small letter lambda] ) present in Ru4+ ions and (2) the sign inversion of [Greek small letter lambda] suggested by Kanamori, the Ruions favors the antiparallel alignment of L and S leading to J = 0. Based on (1) the similarity in the inverse magnetic susceptibility 1/[Greek small letter chi] (T) between CaRuO3 and La2RuZnO6 and (2) the presence of features in CaRuO3 commonly associated with phase fluctuations, the suppression of magnetic moment in Ru4+ is proposed to be responsible for the absence of long-range magnetic ordering in CaRuO3 as well. Finally, the appearance of long-range ferromagnetic ordering in CaRu1-xMxO3 is explained by (1) the degree of hybridization of the Ru4+/Ru5+ redox couple with empty d orbitals and (2) the formation of ferrimagnetic clusters from t2g 3-O- t2g 3 interactions between dopants and localized Ru5+: t2g 3eg 0 configurations. | en_US |
dc.description.department | Electrical and Computer Engineering | en_US |
dc.format.medium | electronic | en_US |
dc.identifier | doi:10.15781/T29C6S604 | |
dc.identifier.uri | http://hdl.handle.net/2152/46246 | |
dc.language.iso | eng | en_US |
dc.relation.ispartof | UT Electronic Theses and Dissertations | en_US |
dc.rights | Copyright © 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.rights.restriction | Restricted | en_US |
dc.subject | Magnetism | en_US |
dc.subject | Electronic transport | en_US |
dc.subject | Electronic structure | en_US |
dc.title | Investigation of electronic transport and magnetic properties in Ca₂-₂xLa₂xRu₂-xCoxO₆ | en_US |
dc.type | Thesis | en_US |
dc.type.genre | Thesis | en_US |