Speaker
Dr
Patrick Clancy
(University of Toronto)
Description
We have performed resonant inelastic x-ray scattering (RIXS) measurements on epitaxial thin film samples of the layered perovskite iridates Ba$_2$IrO$_4$ and Sr$_2$IrO$_4$. These compounds display a novel J$_{eff}$ = 1/2 Mott insulating ground state driven by strong 5d spin-orbit coupling effects. By studying 10 to 50 nm thin film samples grown on a variety of different substrates (GSO, STO, LSAT), we have investigated the impact of applied tensile and compressive strain on the characteristic magnetic and electronic excitations of these materials. Unlike other perturbations, such as doping or applied magnetic field, we find that epitaxial strain does not alter the magnetic structure of Ba$_2$IrO$_4$ or Sr$_2$IrO$_4$. However, applied strain does affect the magnetic energy scales of these systems, providing a means of tuning both the ordering temperature (T$_N$) and the strength of the magnetic exchange interactions (J). Most strikingly, we demonstrate that RIXS can be used to perform detailed magnetic dispersion measurements on thin film samples of 10 nm (~4 unit cells) or less.
Author
Dr
Patrick Clancy
(University of Toronto)
Co-authors
Prof.
Ambrose Seo
(University of Kentucky)
Ms
Andreea Lupascu
(University of Toronto)
Prof.
Darrell Schlom
(Cornell University)
Prof.
Gang Cao
(University of Kentucky)
Prof.
Hermann Stoll
(University of Stuttgart)
Dr
Hlynur Gretarsson
(University of Toronto)
Ms
Jasminka Terzic
(University of Kentucky)
Prof.
Jeroen Van den Brink
(IFW Dresden)
Mr
John Nichols
(University of Kentucky)
Dr
Jungho Kim
(Argonne National Laboratory)
Prof.
Kyle Shen
(Cornell University)
Dr
Liviu Hozoi
(IFW Dresden)
Dr
Mary Upton
(Argonne National Laboratory)
Dr
Masaki Uchida
(Cornell University)
Mr
Vamshi Katukuri
(IFW Dresden)
Prof.
Young-June Kim
(University of Toronto)
Dr
Zahir Islam
(Argonne National Laboratory)
