The Rashba Scale: Emergence of Band Anti-crossing as a Design Principle for Materials with Large Rashba Coefficient
The Rashba Scale: Emergence of Band Anti-crossing as a Design Principle for Materials with Large Rashba Coefficient
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DOI：
10.1016/j.matt.2020.05.006
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发表时间：
2020-07-01
期刊：
影响因子：
18.9
通讯作者：
Zunger, Alex
中科院分区：
文献类型：
--
作者：
Acosta, Carlos Mera;Ogoshi, Elton;Zunger, Alex
低对称性化合物中自旋-轨道诱导的能带自旋分裂（拉什巴效应）与自旋电子学应用和固体对称性破缺的基本理解有着长期的相关性，但在不同材料中控制其大小的知识很难预测。事实上，具有大Rashba系数的化合物的罕见发现总是被视为惊喜。我们提前理解的“Rashba标度”使用“逆设计”的方法，从理论上制定相关的设计原则，然后确定化合物满足it. We表明，存在的能带反交叉提供了一个因果关系的设计原则的化合物与大Rashba系数，导致识别通过第一原理计算的34合理设计的强Rashba化合物。由于拓扑绝缘体必须具有带反交叉，这建立了“拓扑Rashba绝缘体”的有趣交叉功能，可以为同时控制自旋分裂和自旋极化提供平台。
The spin-orbit-induced spin splitting of energy bands in low-symmetry compounds (the Rashba effect) has a long-standing relevance to spintronic applications and the fundamental understanding of symmetry breaking in solids, yet the knowledge of what controls its magnitude in different materials is difficult to anticipate. Indeed, rare discoveries of compounds with large Rashba coefficients are invariably greeted as pleasant surprises. We advance the understanding of the "Rashba Scale" using the "inverse design" approach by formulating theoretically the relevant design principle and then identifying compounds satisfying it. We show that the presence of energy band anti-crossing provides a causal design principle of compounds with large Rashba coefficients, leading to the identification via first-principles calculations of 34 rationally designed strong Rashba compounds. Since topological insulators must have band anti-crossing, this establishes an interesting cross-functionality of "topological Rashba insulators" that may provide a platform for the simultaneous control of spin splitting and spin polarization.