1] Department of Physics, Budapest University of Technology and Economics, Budapest, Hungary [2] Department of Materials Physics, Eötvös University, Budapest, Hungary.
Sci Rep. 2013 Nov 20;3:3233. doi: 10.1038/srep03233.
Spintronics is an emerging paradigm with the aim to replace conventional electronics by using electron spins as information carriers. Its utility relies on the magnitude of the spin-relaxation, which is dominated by spin-orbit coupling (SOC). Yet, SOC induced spin-relaxation in metals and semiconductors is discussed for the seemingly orthogonal cases when inversion symmetry is retained or broken by the so-called Elliott-Yafet and D'yakonov-Perel' spin-relaxation mechanisms, respectively. We unify the two theories on general grounds for a generic two-band system containing intra- and inter-band SOC. While the previously known limiting cases are recovered, we also identify parameter domains when a crossover occurs between them, i.e. when an inversion symmetry broken state evolves from a D'yakonov-Perel' to an Elliott-Yafet type of spin-relaxation and conversely for a state with inversional symmetry. This provides an ultimate link between the two mechanisms of spin-relaxation.
自旋电子学是一种新兴的范例，旨在通过利用电子自旋作为信息载体来取代传统电子学。它的实用性依赖于自旋弛豫的大小，而自旋弛豫主要由自旋轨道耦合（SOC）决定。然而，在保持或破坏所谓的 Elliott-Yafet 和 D'yakonov-Perel'自旋弛豫机制的情况下，金属和半导体中的 SOC 诱导的自旋弛豫分别在看似正交的情况下进行讨论。我们基于一般原理，将这两种理论统一到包含内带和带间 SOC 的通用双能带系统中。虽然恢复了以前已知的限制情况，但我们还确定了它们之间发生交叉的参数域，即当一个反转对称性被破坏的状态从 D'yakonov-Perel'类型的自旋弛豫演变为 Elliott-Yafet 类型的自旋弛豫，反之亦然，对于具有反转对称性的状态。这为两种自旋弛豫机制之间提供了最终的联系。
