Functional Properties of Ferroic Domain Walls

铁性材料，特别是多铁性材料，由于其磁性、电性和弹性之间的潜在耦合而产生的激发特性，近年来得到了广泛的研究。通常出现在这些材料中的畴壁（DW）本质上是二维纳米物体，其通常具有与主体材料不同的性质。从历史上看，DW的属性被简单地忽略了，因为研究集中在域本身的控制和行为上。域之间的边界被认为是意义不大的次要微观结构成分。直到最近才显示DW可能显示出与主体材料不同的功能特性。它们可能是极性的，而主体材料不是1，导电2，甚至当周围是绝缘的时候是导电的。3所发现的最重要的效应之一与畴壁处的增强的电子输运有关。金属属性，2D电子气和自旋输运4已被要求，但到目前为止，几乎没有做过深入的表征的电子输运在DWs.The项目旨在主要了解铁性畴壁的电子输运和传导机制，以及其他功能特性，如自旋或热输运。该研究计划包括。确定最合适的宏观和纳米表征方法，以确定DWs的目标功能特性。基于我们的新型低温矢量磁场和光辅助扫描探针显微镜开发表征方法。我们特别致力于开发飞行时间和纳米霍尔实验，以绘制畴壁处的载流子电荷密度、迁移率和扩散系数。货车Aert，S.特纳河Delville，D. Schryvers，G.货车Tendeloo，E. K. H.萨列，副院长。2012，24，523。2 J. Seidel等人，自然之母。2009，8，229. 3 A.艾尔德，M. C. Domeneghetti，F. Mazzi，V. Tazzoli，E. K. H. Salje，J. Phys. Cond.所谓了1998，10，L569. 4 J. H.李岛，智-地Fina，X. Marti，Y. H. Kim，D.黑森和M. Alexe，Advanced Materials 26，7078（2014）.

Ferroic and especially multiferroic materials have been intensively investigated in the last years for their exciting properties mostly given by the potential coupling between magnetic, electric and elastic properties. Domain walls (DWs) that usually occur in these materials are intrinsically two dimensional nano-objects which usually possess different properties than the host material. Historically, DWs properties were simply disregarded, as the research focused on the control and behaviour of the domains themselves. Boundaries between domains were dismissed as minor microstructural components of little significance. Only very recently has been shown that DWs might show functional properties different than the host material. They might be polar while the host material is not1, conductive2, or even superconductive when the surrounding is insulating.3One of the most important effects discovered was related to enhanced electronic transport at the domain walls. Metallic properties, 2D electron gas and spin transport 4 have been claimed, but so far little has been done to achieve an in-depth characterisation of the electronic transport at the DWs.The project seeks primarily to understand electronic transport and conduction mechanisms at the ferroic domain walls, as well as other functional properties such as spin or heat transport. The research program comprisesI. Identifying most appropriate both macroscopic and nanoscopic characterisation methods to determine the targeted functional properties of DWs.II. Developing characterisation methods based on our new low-temperature vector magnetic field and light assisted scanning probe microscope. We specifically aim to develop time-of-flight and nano-Hall experiments to map carrier charge density, mobility and diffusion coefficient at domain walls.References: 1 S. Van Aert, S. Turner, R. Delville, D. Schryvers, G. Van Tendeloo, E. K. H. Salje, Adv. Mater. 2012, 24, 523. 2 J. Seidel, et al., Nature Mater. 2009, 8, 229. 3 A. Aird, M. C. Domeneghetti, F. Mazzi, V. Tazzoli, E. K. H. Salje, J. Phys. Cond. Matter. 1998, 10, L569. 4 J. H. Lee, I. Fina, X. Marti, Y. H. Kim, D. Hesse, and M. Alexe, Advanced Materials 26, 7078 (2014).