| dc.identifier.uri | http://hdl.handle.net/11401/78146 | |
| dc.description.sponsorship | This work is sponsored by the Stony Brook University Graduate School in compliance with the requirements for completion of degree | en_US |
| dc.format | Monograph | |
| dc.format.medium | Electronic Resource | en_US |
| dc.language.iso | en_US | |
| dc.type | Dissertation | |
| dcterms.abstract | Functional complex-oxides display a wide spectrum of physical properties, including ferromagnetism, piezoelectricity, ferroelectricity, photocatalytic and metal-insulating transition (MIT) behavior. Within this family, oxides with a perovskite structure have been widely studied, especially in the form of thin films and superlattices (heterostructures), which are strategically and industrially important because they offer a wide range of opportunities for electronic, piezoelectric and sensor applications. The first part of my thesis focuses on understanding and tuning of the built-in electric field found in PbTiO3/SrTiO3 (PTO/STO) ferroelectric superlattices and other ferroelectric films. The artificial layering in ferroelectric superlattices is a potential source of polarization asymmetry, where one polarization state is preferred over another. One manifestation of this asymmetry is a built-in electric field associated with shifted polarization hysteresis. Using off-axis RF-magnetron sputtering, we prepared several compositions of PTO/STO superlattice thin films; and for comparison PbTiO3/SrRuO3 (PTO/SRO) superlattices, which have an additional intrinsic compositional asymmetry at the interface. Both theoretical modeling and experiments indicate that the layer-by-layer superlattice structure aligns the Pb-O vacancy defect dipoles in the ?? direction which contributes significantly to the built-in electric field; however the preferred polarization direction is different between the PTO/STO and PTO/SRO interface. By designing a hybrid superlattice that combines PTO/STO and PTO/SRO superlattices, we show the built-in electric field can be tuned to zero by changing the composition of the combo-superlattice. The second part of my thesis focuses on the epitaxial growth of SrCrO3 (SCO) films. The inconsistent reports regarding its electrical and magnetic properties through the years stem from the compositionally and structurally ill-defined polycrystalline samples, but still suggest strong coupling between structure and electronic structure of the material. Our goal is to establish the growth parameters necessary to achieve high-quality and single-phase epitaxial SCO films. Well-defined SCO films were deposited on different substrates to change the structural properties and epitaxial strain. Temperature-dependent resistivity measurements using the Van der Pauw method were performed to identify the metallicity of the films. The results showed a difference in the electrical properties of SCO films under different epitaxial strains. | |
| dcterms.available | 2018-03-22T22:39:08Z | |
| dcterms.contributor | Gersappe, Dilip | en_US |
| dcterms.contributor | Dawber, Matthew. | en_US |
| dcterms.contributor | Venkatesh, T. | en_US |
| dcterms.contributor | Camino, Fernando. | en_US |
| dcterms.creator | Hsing, Greg Hsiang-Chun | |
| dcterms.dateAccepted | 2018-03-22T22:39:08Z | |
| dcterms.dateSubmitted | 2018-03-22T22:39:08Z | |
| dcterms.description | Department of Materials Science and Engineering. | en_US |
| dcterms.extent | 114 pg. | en_US |
| dcterms.format | Monograph | |
| dcterms.format | Application/PDF | en_US |
| dcterms.identifier | http://hdl.handle.net/11401/78146 | |
| dcterms.issued | 2017-08-01 | |
| dcterms.language | en_US | |
| dcterms.provenance | Made available in DSpace on 2018-03-22T22:39:08Z (GMT). No. of bitstreams: 1
Hsing_grad.sunysb_0771E_13410.pdf: 262567459 bytes, checksum: 95043e20b5fcdff8de6608d95b274e8a (MD5)
Previous issue date: 2017-08-01 | en |
| dcterms.subject | ferroelectric | |
| dcterms.subject | Materials Science -- Condensed matter physics. | |
| dcterms.subject | metal-to-insulator transisiton | |
| dcterms.subject | sputtering | |
| dcterms.subject | thin films | |
| dcterms.title | Strain and Defect Engineering for Tailored Electrical Properties in Perovskite Oxide Thin Films and Superlattices | |
| dcterms.type | Dissertation | |
