title: Orbital-ordering transition in Sr2VO4.
abstract: Temperature-dependent dc susceptibility and x-ray powder diffraction on a pure tetragonal sample of Sr(2)VO(4) show an antiferromagnetic orbital-ordering transition at T(oo) = 97 K, in which the occupied orbitals lie along the c axis. The unusual broadening of the x-ray Bragg peaks throughout the orbital-ordering transition temperature region indicates that this process occurs in stages, and the onset of short-range orbital ordering occurs at T(1) approximately 122 K. The study of the order parameter associated with this transition by analyzing the spontaneous strain results in a critical exponent beta = 0.35(2) consistent with 3D Heisenberg behavior. These results experimentally confirm the orbital-ordering state in Sr(2)VO(4) predicted by first-principles calculations using combinations of the local-density approximation and the GW method.
authors.affiliation: Department of Physics, Florida State University, Tallahassee, Florida 32306-3016, USA.
authors.forename: H D
authors.initials: HD
authors.lastname: Zhou
authors.forename: B S
authors.initials: BS
authors.lastname: Conner
authors.forename: L
authors.initials: L
authors.lastname: Balicas
authors.forename: C R
authors.initials: CR
authors.lastname: Wiebe