Joint Physics Dept - MtSE Seminar
May 9th, Tuesday (**SPECIAL DAY**)
Domains and Domain Switching in a Structurally Complex Ferroelectric Oxide
Dr. Elizabeth Nowadnick
School of Applied and Engineering Physics, Cornell University
(Theoretical Condensed Matter Physics, Host: Tyson)
**SPECIAL TIME: 2:45 pm - 3:45 pm with 2:30 pm tea time
**SPECIAL ROOM: Campus Center Room 215
Complex oxides exhibit an incredible diversity of properties ranging from ferroelectricity and ferromagnetism to unconventional superconductivity. Coupling or competition between spin, charge, orbital, and structural order parameters in these materials can lead to new properties and functionality. For example, a coupling between polarization and other order parameters in ferroelectric materials can enable electric field control of non-polar orders. Furthermore, these couplings can stabilize fascinating nanoscale structures in the ferroic domain patterns, such as domain wall vortices. In this talk, I will discuss a recently discovered type of ferroelectricity in layered perovskite Ca3Ti2O7, where the polarization is induced by a coupling to two structural distortions of different symmetry. I will show how a combination of group theoretic analysis and density functional theory calculations can elucidate aspects of the complex domain structure and domain switching processes in Ca3Ti2O7 (and related materials), and also describe scenarios for nanoscale structural order at the domain walls.
Biography: Dr. Elizabeth Nowadnick is a Postdoctoral Research Associate in the School of Applied and Engineering Physics at Cornell University. Her research uses a combination of quantum mechanical simulations and theoretical approaches to advance our fundamental understanding of the properties and functionality of complex oxides and other quantum materials. In particular, she is interested in the physics of materials with multiple competing or coupled order parameters, and has conducted research on systems ranging from high-temperature superconductors to new ferroelectrics. Beth obtained both her B.S. in Physics and Mathematics and her Ph.D. in Physics from Stanford University.