项目名称： 石墨烯中自旋相关的边缘态及其输运调控机理及应用的研究

项目编号： No.11464011

项目类型： 地区科学基金项目

立项/批准年度： 2015

项目学科： 数理科学和化学

项目作者： 刘正方

作者单位： 华东交通大学

项目金额： 45万元

中文摘要： 自从实验报道石墨烯掺入Ni(111)和Au 可获得225meV 的Rashba 自旋轨道耦合后，自旋轨道耦合的研究就引起人们极大的兴趣。尽管Rashba 自旋轨道耦合能够产生自旋进动，然而同时导致体系透射衰减。最近研究发现面内有效交换场不仅能产生自旋进动，还能诱导自旋克莱茵隧穿。因此本研究以紧束缚能带理论为基础采用非平衡态格林函数和传输矩阵方法研究：面内有效交换场和自旋轨道耦合等对石墨烯自旋相关的边缘态及边缘态输运的调控；另外，石墨烯结构的一个很大优点是它的电子性质与其边缘结构有密切关系，因此进一步研究不同边界的石墨烯纳米带中自旋相关的边缘态输运的调控。本研究的科学意义在于把面内有效交换场、自旋轨道耦合与结构结合起来考虑，这样能更加全面系统地进行研究，进而揭示自旋调控的物理机理以及发现奇异的自旋现象，为今后设计优良自旋电子学器件奠定理论基础。

中文关键词： 石墨烯；边缘态输运；边缘态；面内有效交换场；自旋轨道耦合

英文摘要： Since experiments reported that in the mono-graphene film doped by Ni (111) and Au the strength of Rashba spin-orbit coupling can reach 225meV, the study of spin-orbit coupling caused a great deal of interest. Although the Rashba spin-orbit coupling can produce spin precession, the attenuation of the transmission is inevitably caused.Recently, study found that the in-plane effective exchange field can not only produce the spin precession, but also induce a spin-dependent Klein tunneling. So in this study, the tight-binding theory, the non-equilibrium Green's function method and the transfer matrix method are introduced to study: the roles of in-plane efficient exchange field and spin-orbit coupling in modulations of spin-dependent edge state and edge-state state transport in graphene-based micro-nano structure. In addition, a great advantage of graphene nanostructures is that its electronic properties is closely related to the edge structure, so further the modulation of edge-state transport is studied in different graphene nanoribbon. The scientific significance of this study is the in-plane effective exchange field, the spin-orbit coupling and structure are considered together. This can be more comprehensive and systematic to study the spin-dependent phenomena, thus reveal the physical mechanism of spin modulation and find the strange spin-dependent phenomenon, which can lay a theoretical foundation for the future design of excellent spintronics devices.

英文关键词： graphene;edge-state transport;edge state;in-plane efficient exchange field;spin-orbit coupling