Fiebig M, Lottermoser Th, Fröhlich D, Goltsev A V, Pisarev R V
Institut für Physik, Universität Dortmund, 44221 Dortmund, Germany.
Nature. 2002 Oct 24;419(6909):818-20. doi: 10.1038/nature01077.
Ferroelectromagnets are an interesting group of compounds that complement purely (anti-)ferroelectric or (anti-)ferromagnetic materials--they display simultaneous electric and magnetic order. With this coexistence they supplement materials in which magnetization can be induced by an electric field and electrical polarization by a magnetic field, a property which is termed the magnetoelectric effect. Aside from its fundamental importance, the mutual control of electric and magnetic properties is of significant interest for applications in magnetic storage media and 'spintronics'. The coupled electric and magnetic ordering in ferroelectromagnets is accompanied by the formation of domains and domain walls. However, such a cross-correlation between magnetic and electric domains has so far not been observed. Here we report spatial maps of coupled antiferromagnetic and ferroelectric domains in YMnO3, obtained by imaging with optical second harmonic generation. The coupling originates from an interaction between magnetic and electric domain walls, which leads to a configuration that is dominated by the ferroelectromagnetic product of the order parameters.
铁电磁体是一类有趣的化合物，它补充了纯（反）铁电或（反）铁磁材料——它们同时呈现电有序和磁有序。这种共存特性补充了那些能通过电场诱导磁化以及通过磁场诱导电极化的材料，这一特性被称为磁电效应。除了其基本重要性外，电性能和磁性能的相互控制对于磁存储介质和“自旋电子学”中的应用也具有重大意义。铁电磁体中耦合的电有序和磁有序伴随着畴和畴壁的形成。然而，迄今为止尚未观察到磁畴和电畴之间存在这种相互关联。在此，我们报告了通过光学二次谐波成像获得的YMnO₃中反铁磁畴和铁电畴耦合的空间分布图。这种耦合源于磁畴壁和电畴壁之间的相互作用，这导致了一种由序参量的铁电磁乘积主导的结构。
