title: One Dimensional(1D)-to-2D Crossover of Spin Correlations in the 3D Magnet ZnMn2O4.
abstract: We report on the intriguing evolution of the dynamical spin correlations of the frustrated spinel ZnMn2O4. Inelastic neutron scattering and magnetization studies reveal that the dynamical correlations at high temperatures are 1D. At lower temperature, these dynamical correlations become 2D. Surprisingly, the dynamical correlations condense into a quasi 2D Ising-like ordered state, making this a rare observation of two dimensional order on the spinel lattice. Remarkably, 3D ordering is not observed down to temperatures as low as 300 mK. This unprecedented dimensional crossover stems from frustrated exchange couplings due to the huge Jahn-Teller distortions around Mn(3+) ions on the spinel lattice.
authors.affiliation: NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899.
authors.forename: S M
authors.initials: SM
authors.lastname: Disseler
authors.affiliation: NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899.|Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742.
authors.forename: Y
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Rutgers Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854.|Korea Atomic Energy Research Institute, Daejeon, Korea.
authors.forename: S
authors.initials: S
authors.lastname: Yeo
authors.affiliation: NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899.|Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742.
authors.forename: G
authors.initials: G
authors.lastname: Gasparovic
authors.affiliation: Intense Pulsed Neutron Source, Argonne National Laboratory, Argonne, Illinois 60439.
authors.forename: P M B
authors.initials: PM
authors.lastname: Piccoli
authors.affiliation: Intense Pulsed Neutron Source, Argonne National Laboratory, Argonne, Illinois 60439.
authors.forename: A J
authors.initials: AJ
authors.lastname: Schultz
authors.affiliation: NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899.|Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742.
authors.forename: Y
authors.initials: Y
authors.lastname: Qiu
authors.affiliation: NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899.
authors.forename: Q
authors.initials: Q
authors.lastname: Huang
authors.affiliation: Rutgers Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854.
authors.forename: S-W
authors.initials: SW
authors.lastname: Cheong
authors.affiliation: NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899.
authors.forename: W
authors.initials: W
authors.lastname: Ratcliff