February 2
@
4:00 PM
–
5:00 PM
Dr. Caroline Ross
Department of Materials Science and Engineering
Massachusetts Institute of Technology
Host: Professor Jiamian Hu (MS&E)
Magnetic insulators for spintronic, photonic and magnetoelectric devices
Abstract
Magnetic insulator thin films provide unique functionality in spintronic, magnonic, and magnetooptical devices such as magnetic memory, magnetic logic, and photonic integrated circuits. Iron garnets exemplified by yttrium iron garnet are ferrimagnetic insulators with a wide range of properties manipulated by cation substitution. We use pulsed laser deposition to produce films and multilayers of rare earth and Bi-substituted garnets and garnet/metal heterostructures with tunable magnetic anisotropy, damping, and compensation temperatures. These materials reveal a Dzyaloshinskii-Moriya interaction that yields chiral domain walls, and high-speed domain wall motion driven by spin orbit torques or by spin waves. Iron garnets also exhibit magnetooptical activity and high transparency in the infrared, and we show how garnets grown on silicon can be used in integrated magnetooptical isolators to control the flow of light in photonic circuits. Finally, we will describe a new class of multiferroic perovskites where ferroelectricity is introduced using antisite defects.
Biography
Caroline Ross has been a professor at the Massachusetts Institute of Technology since 1997, and is currently the Associate Head of the Department of Materials Science and Engineering. Before joining MIT she spent six years working at Komag, Inc. in San Jose, CA and two years as a Postdoctoral Fellow at Harvard University. She has a Bachelor’s degree and a Ph.D. from Cambridge University, UK. She is a Fellow of the APS, the MRS, the UK Institute of Physics and the IEEE and was the Chair of the 2011 Magnetism and Magnetic Materials Conference.