微波场作用下石墨烯二维电子气的量子输运研究

项目名称： 微波场作用下石墨烯二维电子气的量子输运研究

项目编号： No.11304299

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 数理科学和化学

项目作者： 魏来明

作者单位： 中国科学技术大学

项目金额： 25万元

中文摘要： 研究石墨烯二维电子气的量子输运性质对设计基于石墨烯的新型量子器件具有重要意义。本项目将使用微机械剥离法从石墨上剥离石墨烯，并将其转移到硼氮衬底上，制备高迁移率单层石墨烯。通过电子束光刻制备Hall bar结构并加工栅极。通过微波辐照下的低温磁输运测试，研究微波对石墨烯量子输运行为（量子霍尔效应、Shubnikov-de Haas振荡、弱局域和反弱局域效应等）的影响。致力于在石墨烯体系中观察到微波场引起的新颖效应（微波诱发磁阻振荡（MIRO）和零电阻态（ZRS）、磁致等离激元共振（MPR）、电子自旋共振（ESR）、微波引起电子退相等）。由此获得载流子有效质量、g因子、输运迁移率和量子迁移率、自旋弛豫时间、退相干时间、谷内和谷间散射时间等重要物理量，并研究微波场和栅压对这些物理量的调控作用。本项目有希望发现石墨烯在微波场作用下的新奇物理效应和调控规律，为新型材料和自旋电子学的发展提供有用参考。

中文关键词： 石墨烯；微波；二维电子气；磁输运；

英文摘要： The quantum transport properties of the two-dimension electron gas in graphene are very important for the design of new quantum devices based on graphene. In this project, we will prepare high mobility graphene monolayers by micromechanical cleavage of graphite and transferring graphene to boron nitride substrates. The samples will be processed into the standard Hall bar structure using electron beam lithography and the gate electrode will also be fabricated. By means of magnetotransport measurements at low temperature under microwave illumination, we will investigate the microwave influence on the quantum transport behavior of graphene, for example, quantum Hall effect, Shubnikov-de Haas oscillations, weak localization and weak antilocalization effect. We will devote ourselves to explore new phenomena induced by microwave fields in graphene systems, for example, microwave-induced resistance oscillations (MIRO) and zero-resistance states (ZRS), magnetoplasmon resonance (MPR), electron spin resonance (ESR), microwave-induced dephasing and so on. We will not only extract some important physical parameters such as effective mass, g-factor, transport/quantum mobility, spin relaxation time, dephasing time and intra-/inter-valley scattering time, but also investigate the modulation of these parameters by microwave fie

英文关键词： graphene；microwave；two-dimensional electron gas；magnetotransport；