Ryan D H, Rejali Rasa, Cadogan J M, Flacau R, Boyer C D
Physics Department and Centre for the Physics of Materials, McGill University, 3600 University Street, Montreal, Quebec, H3A 2T8, Canada.
J Phys Condens Matter. 2016 Apr 27;28(16):166003. doi: 10.1088/0953-8984/28/16/166003. Epub 2016 Mar 24.
The antiferromagnetic structures of both the manganese and europium sublattices in EuMn2Ge2 have been determined using thermal neutron diffraction. T(N)(Mn) = 714(5) K with the 3.35(5) μ(B) (at 285 K) Mn moments ordering according to the I4'/m'm'm space group. The Eu order is incommensurate with the 6.1(2) μ(B) (at 3.6 K) Eu moments oriented parallel to the c-axis with a propagation vector of k = [0.153(2) 0 0]. Both neutron diffraction and (151)Eu Mössbauer spectroscopy reveal evidence of magnetic short-range ordering of the Eu sublattice around and above T(N)(Eu) ∼ 10 K. The ordering temperature of the Eu sublattice is strongly affected by the sample's thermal history and rapid quenching from the melting point may lead to a complete suppression of that ordering.
利用热中子衍射确定了EuMn2Ge2中锰和铕亚晶格的反铁磁结构。T(N)(Mn) = 714(5) K，3.35(5) μ(B)（在285 K时）的锰磁矩根据I4'/m'm'm空间群有序排列。铕的有序排列与6.1(2) μ(B)（在3.6 K时）的铕磁矩不相称，这些磁矩平行于c轴取向，传播矢量为k = [0.153(2) 0 0]。中子衍射和(151)Eu穆斯堡尔谱都揭示了在T(N)(Eu) ∼ 10 K及以上温度时铕亚晶格磁短程有序的证据。铕亚晶格的有序温度受到样品热历史的强烈影响，从熔点快速淬火可能导致该有序排列被完全抑制。
