Crystal Structure Studies, Electrical and Magnetic Properties of 2, 3, 4, 5-Layer Aurivillius Oxides
Date
2015-02
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
New York State College of Ceramics at Alfred University. Kazuo Inamori School of Engineering.
Abstract
The crystal structures of assorted Aurivillius compositions have been indexed
and refined from combined Neutron and x-ray powder diffraction data. The crystal
structure distortions were discussed quantitatively from mainly three aspects:
octahedron tilt, perovskite in-plane distortion and interlayer adjustment between
perovskite and Bi-O layer. Both A-site cation ionic radius and number of perovskite
layers influence the structure distortion details which is decisive for the spontaneous
polarization. Dielectric, ferroelectric and conductivity measurements were used to link
the structure features with electrical properties. Besides the macroscopic structure
information, local nano-region disorder would affect electrical properties. A series of rare
earth Aurivillius oxides with Mn-doping was studied for possible multiferroic behavior. All
the studied compositions turned out to be paramagnetic with (anti)ferromagnetic
interactions at very low temperature and magnetoresistance was observed.
Description
Advisory Committee Members: Scott Misture, Doreen Edwards, Nathan Mellott, S.K. Sundaram, Walter Schulze. Dissertation completed in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Ceramic Engineering at the Inamori School of Engineering, New York State College of Ceramics at Alfred University
Type
Thesis