Fabrizi F, Walker H C, Paolasini L, de Bergevin F, Boothroyd A T, Prabhakaran D, McMorrow D F
European Synchrotron Radiation Facility, 38043 Grenoble, France.
Phys Rev Lett. 2009 Jun 12;102(23):237205. doi: 10.1103/PhysRevLett.102.237205.
Nonresonant x-ray magnetic scattering has been used to study the magnetic structure of multiferroic TbMnO3 in its ferroelectric phase. Circularly polarized x rays were combined with full polarization analysis of the scattered beam to reveal important new information on the magnetic structure of this canonical multiferroic. An applied electric field is shown to create essentially a single magnetic domain state in which the cycloidal order on the Mn sublattice rotates either clockwise or anticlockwise depending on the sign of the field. It is demonstrated how this technique provides sensitivity to the absolute sense of rotation of the Mn moments and to components of the ordering on the Tb sublattice and phase shifts that earlier neutron diffraction experiments could not resolve.
非共振X射线磁散射已被用于研究多铁性材料TbMnO₃铁电相的磁结构。圆偏振X射线与散射光束的全偏振分析相结合，揭示了关于这种典型多铁性材料磁结构的重要新信息。结果表明，施加电场会产生基本上单一的磁畴状态，其中Mn亚晶格上的摆线序根据电场的符号顺时针或逆时针旋转。证明了该技术如何对Mn磁矩的绝对旋转方向、Tb亚晶格上的有序分量以及早期中子衍射实验无法分辨的相移具有敏感性。
