Magnetic-field-induced transition in the lattice modulation of colossal magnetoelectric GdMnO3 and TbMnO3 compounds
Magnetic-field-induced transition in the lattice modulation of colossal magnetoelectric GdMnO3 and TbMnO3 compounds
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DOI：
10.1103/physrevb.72.100102
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发表时间：
2005-09
影响因子：
3.7
通讯作者：
T. Arima;T. Goto;Y. Yamasaki;S. Miyasaka;K. Ishii;M. Tsubota;T. Inami;Y. Murakami;Y. Tokura-Y.-Toku
中科院分区：
文献类型：
--
作者：
T. Arima;T. Goto;Y. Yamasaki;S. Miyasaka;K. Ishii;M. Tsubota;T. Inami;Y. Murakami;Y. Tokura-Y.-Toku
Single-crystal synchrotron x-ray diffraction measurements in strong magnetic fields have been performed for magnetoelectric compounds $\mathrm{Gd}\mathrm{Mn}{\mathrm{O}}_{3}$ and $\mathrm{Tb}\mathrm{Mn}{\mathrm{O}}_{3}$. It has been found that the $\mathbit{P}\ensuremath{\Vert}a$ ferroelectric phase induced by the application of a magnetic field at low temperatures is characterized by commensurate lattice modulation along the orthorhombic $b$ axis with $q=1∕2$ and $q=1∕4$. The lattice modulation is ascribed to antiferromagnetic spin alignment with a modulation vector of $(0\phantom{\rule{0.3em}{0ex}}1∕4\phantom{\rule{0.3em}{0ex}}1)$. The change of the spin structure is directly correlated with the magnetic-field-induced electric phase transition, because any commensurate spin modulation with $(0\phantom{\rule{0.3em}{0ex}}1∕4\phantom{\rule{0.3em}{0ex}}1)$ should break glide planes normal to the $a$ axis of the distorted perovskite with the $Pbnm$ space group.
Single-crystal synchrotron x-ray diffraction measurements in strong magnetic fields have been performed for magnetoelectric compounds $\mathrm{Gd}\mathrm{Mn}{\mathrm{O}}_{3}$ and $\mathrm{Tb}\mathrm{Mn}{\mathrm{O}}_{3}$. It has been found that the $\mathbit{P}\ensuremath{\Vert}a$ ferroelectric phase induced by the application of a magnetic field at low temperatures is characterized by commensurate lattice modulation along the orthorhombic $b$ axis with $q=1∕2$ and $q=1∕4$. The lattice modulation is ascribed to antiferromagnetic spin alignment with a modulation vector of $(0\phantom{\rule{0.3em}{0ex}}1∕4\phantom{\rule{0.3em}{0ex}}1)$. The change of the spin structure is directly correlated with the magnetic-field-induced electric phase transition, because any commensurate spin modulation with $(0\phantom{\rule{0.3em}{0ex}}1∕4\phantom{\rule{0.3em}{0ex}}1)$ should break glide planes normal to the $a$ axis of the distorted perovskite with the $Pbnm$ space group.