title: Suppression of magnetic coupling by in-plane buckling in SrFeO2.
abstract: SrFeO2 is an insulating antiferromagnet with a remarkably high transition temperature in spite of its quasi-two-dimensional crystal structure. The magnetic exchange coupling is, however, very sensitive to a local mode involving transverse displacements of O and Fe, resulting in zigzag patterns of distortion. The buckling driven by rising temperatures is enhanced just as the Fe magnetic moment is reduced, implying a strong spin-lattice coupling. It is suggested that the undulations lead to orbital disorder by distorting the three possible paths to exchange interactions.
authors.affiliation: Department of Physics, University of Virginia, Charlottesville, Virginia 22904, USA.
authors.forename: Kazumasa
authors.initials: K
authors.lastname: Horigane
authors.affiliation: Lujan Neutron Scattering Center, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
authors.forename: Anna
authors.initials: A
authors.lastname: Llobet
authors.affiliation: Department of Physics, University of Virginia, Charlottesville, Virginia 22904, USA.
authors.forename: Despina
authors.initials: D
authors.lastname: Louca