单层MoS2中的自旋极化输运与调控

项目名称： 单层MoS2中的自旋极化输运与调控

项目编号： No.11304319

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： 杨继勇

作者单位： 中国科学院合肥物质科学研究院

项目金额： 25万元

中文摘要： 随着微纳电子技术的不断深化，集成电路的进一步高密度化和器件的多功能化成为发展的必然趋势，二维材料是未来制备纳米器件的首选。单层MoS2晶体管具有高迁移率、高电流开关比率和低能耗的特性，使得单层MoS2成为制备下一代二维电子器件的最具前景的材料之一。在该基器件中同时实现电荷与自旋的操控，具有重要的意义。操控自旋的基础是材料的自旋轨道耦合要比较强。单层MoS2中的自旋轨道耦合达到了160meV，理论预言其电子的自旋还具有面外极化的特性以及较长的自旋弛豫时间，进一步的理论研究还指出在该体系中可能观测到自旋霍尔效应。是否能够在MoS2实现自旋的操控，是目前亟待解决的问题。本课题中，我们将深入的研究MoS2中自旋轨道耦合诱导的相关极化输运现象，包括极化电流的注入、自旋相干长度的测定、自旋霍尔效应的观测以及自旋极化输运的调控等等，为MoS2基自旋极化输运器件的设计提供重要的实验依据。

中文关键词： MoS2；自旋轨道耦合；器件；调控；过渡金属氧硫化物

英文摘要： With the continuous progress of the micro-nano electronics technology, further high-density integrated circuits and multi-functional devices become the inevitable trend of development, the two-dimensional material is undoubtedly the first choice for future preparation of nano devices. Single layer MoS2 is a direct band gap semiconductor with a band gap of 1.8 eV, the single layer MoS2 based transistor having a high mobility, high current switching ratio, and low power consumption characteristics, making it become one of the most promising materials of the preparation of the next generation two-dimensional electronic device. Control of the charge and spin degrees simultaneously in these devices is extremely important. The basis for controlling the spin degree of freedom requires a strong spin-orbital coupling in the materials. Experimental results showed that in single layer MoS2, the spin-orbital coupling-induced spin splitting in the top of the valence band reaches about 160 meV due to the missing inversion symmetry, which is much larger than typical values in graphene (4 meV) and in the two-dimensional electron gas of conventional III-V and II-VI group semiconductors (30 meV). The most interesting thing is that the electrons in this semiconductor are predicted to be fully out of plane due to the two-dimension

英文关键词： MoS2；spin-orbit coupling；device；control；transition metal chalcogenide or oxide