Domain wall nanoelectronics
Domain wall nanoelectronics
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DOI：
10.1103/revmodphys.84.119
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发表时间：
2012-02-03
影响因子：
44.1
通讯作者：
Scott, J. F.
中科院分区：
文献类型：
--
作者：
Catalan, G.;Seidel, J.;Scott, J. F.
到上个世纪中期，人们对铁电体中的畴有了很好的了解：它们通常是直线形的，畴壁是伊辛型的。他们的简单性与更复杂的布洛赫墙或尼尔墙形成鲜明对比。只是在过去的十年中，随着通过透射电子显微镜、电子全息术和具有偏振灵敏度的原子力显微镜进行的原子分辨率研究的引入，它们的真实的复杂性才被揭示出来。在最近的研究中出现了其他现象，特别是磁电材料，其中畴壁内的功能特性被直接测量。在本文中，这些研究进行了审查，重点关注铁电和多铁性，但在可能的情况下，与磁畴和畴壁进行比较。这次审查的一个重要组成部分将关注设备的应用，与铁电器件的磁畴壁，而不是域，是有源元件的新范例的聚光灯。在这方面，磁壁微电子学已经全面展开，这主要归功于考伯恩和帕金及其同事的工作。这些设备利用了磁体中的高畴壁迁移率及其产生的高速度，如Kreines及其同事30年前所示，这可以是超音速的。相比之下，采用铁电畴壁的纳米电子器件通常具有较慢的畴壁速度，但可以利用其较小的尺寸以及其不同的功能特性。这些包括畴壁导电性（在块状绝缘或半导体氧化物中是金属的甚至是超导的）以及畴壁可以是铁磁的而周围的畴不是铁磁的事实。
Domains in ferroelectrics were considered to be well understood by the middle of the last century: They were generally rectilinear, and their walls were Ising-like. Their simplicity stood in stark contrast to the more complex Bloch walls or Neel walls in magnets. Only within the past decade and with the introduction of atomic-resolution studies via transmission electron microscopy, electron holography, and atomic force microscopy with polarization sensitivity has their real complexity been revealed. Additional phenomena appear in recent studies, especially of magnetoelectric materials, where functional properties inside domain walls are being directly measured. In this paper these studies are reviewed, focusing attention on ferroelectrics and multiferroics but making comparisons where possible with magnetic domains and domain walls. An important part of this review will concern device applications, with the spotlight on a new paradigm of ferroic devices where the domain walls, rather than the domains, are the active element. Here magnetic wall microelectronics is already in full swing, owing largely to the work of Cowburn and of Parkin and their colleagues. These devices exploit the high domain wall mobilities in magnets and their resulting high velocities, which can be supersonic, as shown by Kreines' and co-workers 30 years ago. By comparison, nanoelectronic devices employing ferroelectric domain walls often have slower domain wall speeds, but may exploit their smaller size as well as their different functional properties. These include domain wall conductivity (metallic or even superconducting in bulk insulating or semiconducting oxides) and the fact that domain walls can be ferromagnetic while the surrounding domains are not.