Kagawa F, Mochizuki M, Onose Y, Murakawa H, Kaneko Y, Furukawa N, Tokura Y
Multiferroics Project, ERATO, Japan Science and Technology Agency (JST), c/o Department of Applied Physics, University of Tokyo, Tokyo 113-8656, Japan.
Phys Rev Lett. 2009 Feb 6;102(5):057604. doi: 10.1103/PhysRevLett.102.057604.
We report the dielectric dispersion of the giant magnetocapacitance (GMC) in multiferroic DyMnO3 over a wide frequency range. The GMC is found to be attributable not to the softened electromagnon but to the electric-field-driven motion of multiferroic domain wall (DW). In contrast to conventional ferroelectric DWs, the present multiferroic DW motion holds an extremely high relaxation rate of approximately 10;{7} s;{-1} even at low temperatures. This mobile nature as well as the model simulation suggests that the multiferroic DW is not atomically thin as in ferroelectrics but thick, reflecting its magnetic origin.
我们报道了多铁性材料DyMnO₃中巨磁电容（GMC）在宽频率范围内的介电色散。结果发现，GMC并非归因于软化的电磁子，而是归因于多铁性畴壁（DW）的电场驱动运动。与传统铁电畴壁不同，即使在低温下，目前的多铁性畴壁运动也具有约10⁻⁷ s⁻¹的极高弛豫率。这种可移动特性以及模型模拟表明，多铁性畴壁不像铁电体中的那样原子级薄，而是厚的，这反映了其磁学起源。
