2005/01/17 by Graeme R. Blake, G. R. Blake, L. C. Chapon +8 · 5 citations
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Ferroelectric and Piezoelectric Materials #Multiferroics and related materials #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.71.214402
23 pages
arxiv created 2005/01/17 · openalex publication_date 2005/06/02 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We have studied the crystal and magnetic structures of the magnetoelectric materials RMn2O5 (R=Tb,Ho,Dy) using neutron diffraction as a function of temperature. All three materials display incommensurate antiferromagnetic ordering below 40\phantom\rule0.3em0exK, becoming commensurate on further cooling. For R=Tb,Ho, a commensurate-incommensurate transition takes place at low temperatures. The commensurate magnetic structures have been solved and are discussed in terms of competing exchange interactions. The spin configuration within the ab plane is essentially the same for each system, and the radius of R determines the sign of the magnetic exchange between adjacent planes. The inherent magnetic frustration in these materials is lifted by a small lattice distortion, primarily involving shifts of the Mn3+ cations and giving rise to a canted antiferroelectric phase.