Tuning magnetic coupling in Sr2IrO4 thin films with epitaxial strain.
We report x-ray resonant magnetic scattering and resonant inelastic x-ray scattering studies of epitaxially strained Sr2IrO4 thin films. The films were grown on SrTiO3 and (LaAlO3)0.3(Sr2AlTaO6)0.7 substrates, under slight tensile and compressive strains, respectively. Although the films develop a magnetic structure reminiscent of bulk Sr2IrO4, the magnetic correlations are extremely anisotropic, with in-plane correlation lengths significantly longer than the out-of-plane correlation lengths. In addition, the compressive (tensile) strain serves to suppress (enhance) the magnetic ordering temperature TN, while raising (lowering) the energy of the zone-boundary magnon. Quantum chemical calculations show that the tuning of magnetic energy scales can be understood in terms of strain-induced changes in bond lengths.
Department of Physics, University of Toronto, 60 St. George Street, Toronto, Ontario M5S 1A7, Canada.
A
A
Lupascu
Department of Physics, University of Toronto, 60 St. George Street, Toronto, Ontario M5S 1A7, Canada.
J P
JP
Clancy
Department of Physics, University of Toronto, 60 St. George Street, Toronto, Ontario M5S 1A7, Canada.
H
H
Gretarsson
Department of Physics, University of Toronto, 60 St. George Street, Toronto, Ontario M5S 1A7, Canada.
Zixin
Z
Nie
Department of Physics and Astronomy, University of Kentucky, Lexington, Kentucky 40506, USA.
J
J
Nichols
Department of Physics and Astronomy, University of Kentucky, Lexington, Kentucky 40506, USA.
J
J
Terzic
Department of Physics and Astronomy, University of Kentucky, Lexington, Kentucky 40506, USA.
G
G
Cao
Department of Physics and Astronomy, University of Kentucky, Lexington, Kentucky 40506, USA.
S S A
SS
Seo
Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA.
Z
Z
Islam
Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA.
M H
MH
Upton
Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA.
Jungho
J
Kim
Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA.
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D
Casa
Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA.
T
T
Gog
Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA.
A H
AH
Said
Institute for Theoretical Solid State Physics, IFW Dresden, Helmholtzstrasse. 20, 01069 Dresden, Germany.
Vamshi M
VM
Katukuri
Institute for Theoretical Chemistry, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany.
H
H
Stoll
Institute for Theoretical Solid State Physics, IFW Dresden, Helmholtzstrasse. 20, 01069 Dresden, Germany.
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L
Hozoi
Institute for Theoretical Solid State Physics, IFW Dresden, Helmholtzstrasse. 20, 01069 Dresden, Germany.
J
J
van den Brink
Department of Physics, University of Toronto, 60 St. George Street, Toronto, Ontario M5S 1A7, Canada.
Young-June
YJ
Kim