MSE Seminar Series: Veerle Keppens, University of Tennessee
Friday, February 24, 2017
1:00 p.m.-2:00 p.m.
Room 2110, Chemical and Nuclear Engineering Building
EuTiO3: the magnetic doppelgänger of SrTiO3
The tilting of the oxygen octahedra in cubic perovskites is known to induce structural phase transitions, which are often associated with the emergence of intriguing physical phenomena. While SrTiO3 is one of the most extensively studied perovskite oxides for its structural phase transition at 105 K, the discovery of magnetoelectric coupling in isostructural EuTiO3 has triggered many theoretical and experimental studies focused on this compound. I will present resonant ultrasound studies of the extremely subtle cubic to tetragonal structural phase transition at 288 K in EuTiO3 single crystals and the evolution of the physical properties upon chemical doping. The collective set of experimental data contributes to a better understanding of the link between lattice, magnetic and electrical degrees of freedom in the EuTiO3 system, helps evaluate the similarities and differences between SrTiO3 and EuTiO3, and provides insight in the possible origin of the much higher structural transition temperature for EuTiO3 compared to SrTiO3.
Veerle Keppens earned her bachelor’s degree (1989) and Ph.D. (1995) in Physics from the Katholieke Universiteit Leuven (Belgium). From 1995 to 1998, Dr. Keppens was a Fulbright fellow in the novel materials group at Oak Ridge National Laboratory, where she became interested in the elastic properties of new materials. In 1999, she joined the faculty in the Physics Department at The University of Mississippi. In 2003, she moved back to Tennessee and joined the faculty in the materials science and engineering department at the University of Tennessee, where she continues to study the elastic properties and lattice dynamics of novel materials. At UT, she has received multiple awards at the departmental, college, and campus level, and in 2011 she became a fellow of the Acoustical Society of America for the application of ultrasonics to materials physics. She served as the associate dean for faculty affairs from August 2012 till October 2016. In 2015, she became the department head for the department of Materials Science and Engineering (MSE) and in June of 2016, she was appointed as the director of the Joint Institute for Advanced Materials (JIAM), a position she combines with that of MSE department head.