Magnetic phase diagram and ordered ground state of GdMn2O5 multiferroic studied by x-ray magnetic scattering

Workshop on Resonant Elastic X-ray Scattering in Condensed Matter 2013

Vecchini, C.^1,2 ; Bombardi, A.^1 ; Chapon, L.C.^3,4 ; Lee, N.^5 ; Radaelli, P.G.^6 ; Cheong, S.-W.^5

Diamond Light Source Ltd, Harwell Science and Innovation Campus, Oxfordshire, OX11 0DE, Didcot, United Kingdom^1

National Physical Laboratory, Hampton Road, Teddington, TW11 0LW, United Kingdom^2

Institut Laue-Langevin, BP 156X, 38042, Grenoble, France^3

ISIS Facility, Rutherford Appleton Laboratory-STFC, OX11 0QX, Didcot Chilton, United Kingdom^4

Rutgers Center for Emergent Materials, Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854, United States^5

Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom^6

关键词: Magnetic phase diagrams;    Magnetic propagation;    Magnetic sublattices;    Precise determinations;    Resonant condition;    Superexchange interaction;    Temperature dependence;    X-ray magnetic scattering;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/519/1/012004/pdf
DOI  :  10.1088/1742-6596/519/1/012004

来源: IOP

【 摘 要 】

The magnetic structure of multiferroic GdMn2O5 is studied by x-ray magnetic scattering, both off resonance and in resonant conditions at the Gd LIII edge. Temperature dependence of magnetic Bragg reflections shows an initial incommensurate (ICM) ordering appearing at T∼40K with magnetic propagation vector kICM ∼(0.49 0 0.18) which condenses at T∼33K in a commensurate (CM) wave vector kCM=(1/2 0 0). In the CM phase Gd3+ions appear to order spontaneously at the same temperature as Mn ions. Azimuthal scans allowed for the precise determination, from x-ray magnetic scattering only, of the orientation and magnitude of the Gd3+magnetic moments. The Gd3+magnetic isotropy allows for the Gd ions to mimic the Mn4+magnetic sublattice via Gd-Mn-Gd superexchange interactions.