Harnessing the power of topology in oxide electronics for future IT components

尽管硅(CMOS)技术在推动IT革命方面取得了非凡的成功，但它本质上并不节能，因为它依赖于电荷的运动，而电荷运动与焦耳加热有关。自旋电子学是超cmos技术中的领跑者之一，它依靠自旋而不是电荷来传输和处理信息；然而，如果自旋翻转--基本的自旋电子学操作--本身必须通过电流来执行，那么自旋电子学的大部分能效就会损失。因此，磁性元件的电压控制被广泛认为是自旋电子学大规模商业化的关键[1-3]。氧化物电子学领域正是源于这样一种考虑，即氧化物，特别是那些含有磁性过渡金属离子(如Co，Mn和Fe)的氧化物，在其绝缘状态下可以显示出许多有趣的电控多功能特性，而与CMOS的集成已经成为现实。通过利用拓扑学的力量，氧化物电子的潜力可以进一步增强，确切地说，拓扑学涉及将自旋捆绑成“磁结”。在最近发表在《自然材料》[4]上的工作中，由保罗·G·拉代利教授(牛津物理)领导的一个国际合作者团队在该领域[5]取得了重大突破：他们首次创造了小型氧化物/金属拓扑磁性物体，由反铁磁性氧化铁(a-Fe2O3)和铁磁性金属钴(Co)中的紧密耦合自旋涡旋组成。这种系统的一个特别吸引人的特点是它使用了廉价和容易获得的材料(a-Fe2O3是常见铁锈中含量最丰富的成分！)而且制造相对简单，这让人们对这些系统未来可以进行商业规模的部署产生了希望。这个由EPSRC资助的DPHIL项目将使成功的应聘者有机会在不同的方向发展这一研究领域，包括基础和应用。该项目属于EPSRC量子设备组件和系统主题。

In spite of its extraordinary success in fuelling the IT revolution, silicon (CMOS) technology is intrinsically not energy-efficient, because it relies on the movement of electrical charge, which is associated with Joule heating. One of the front runners among 'beyond-CMOS' technologies is spintronics, which relies on spins rather than charges to transfer and process information; however, much of the energy efficiency of spintronics is lost if spin flipping - the elementary spintronic operation - must in itself be performed by electrical currents. For this reason, voltage control of magnetic components is widely considered to be the key to large-scale commercialisation of spintronics [1-3]. The field of oxide electronics emerges precisely from the consideration that oxides, especially those containing magnetic transition metal ions such as Co, Mn and Fe, can display a multitude of intriguing electrically-controlled multi-functional properties in their insulating states, whilst integration with CMOS is already a reality. The potential of oxide electronics can be further enhanced by exploiting the power of topology, which involves, quite literally, tying spins into 'magnetic knots'. In work recently published in Nature Materials [4], an international team of collaborators lead by Professor Paolo G. Radaelli (Oxford Physics) presented a major breakthrough in this field [5]: they created, for the first time, small-scale hybrid oxide/metal topological magnetic objects, consisting of tightly-coupled spin vortices in antiferromagnetic iron oxide (a-Fe2O3) and ferromagnetic metallic cobalt (Co). One particularly appealing feature of this system is that it employs cheap and readily available materials (a-Fe2O3 is the most abundant constituent of common rust!) and relatively simple fabrication, raising hopes that these systems could be deployed on a commercial scale in the future. This EPSRC-funded DPhil project will give the successful candidate the opportunity to develop this line of research in different directions, both fundamental and applied.This project falls under the EPSRC Quantum devices components and systems theme.