Department of Physics and Astronomy and Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA.
Phys Rev Lett. 2011 Feb 25;106(8):087202. doi: 10.1103/PhysRevLett.106.087202. Epub 2011 Feb 23.
We report the direct observation of surface magnetization domains of the magnetoelectric Cr(2)O(3) using photoemission electron microscopy with magnetic circular dichroism contrast and magnetic force microscopy. The domain pattern is strongly affected by the applied electric field conditions. Zero-field cooling results in an equal representation of the two domain types, while electric-field cooling selects one dominant domain type. These observations confirm the existence of surface magnetization, required by symmetry in magnetoelectric antiferromagnets.
我们利用具有磁圆二色性对比和磁力显微镜的光发射电子显微镜直接观察了磁电 Cr(2)O(3)的表面磁化畴。畴图案强烈受到施加电场条件的影响。零场冷却导致两种畴类型的均匀表示,而电场冷却则选择一种主导畴类型。这些观察结果证实了磁电反铁磁体中对称性所要求的表面磁化的存在。