蒽二噻吩分子连接铁磁锯齿边碳化硅纳米带的巨幅度自旋整流  

Giant rectification of ferromagnetic zigzag SiC nanoribbons connecting anthradithiophene molecules

作　　者：李佳锦 刘乾 伍丹 邓小清[1] 张振华[1] 范志强[1] Li Jia-Jin;Liu Qian;Wu Dan;Deng Xiao-Qing;Zhang Zhen-Hua;Fan Zhi-Qiang(Hunan Provincial Key Laboratory of Flexible Electronic Materials Genome Engineering,School of Physics and Electronic Science,Changsha University of Science and Technology,Changsha 410114,China)

机构地区：[1]长沙理工大学物理与电子科学学院,柔性电子材料基因工程湖南省重点实验室,长沙410114

出　　处：《物理学报》2022年第7期347-355,共9页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:12074046,61771076);湖南省自然科学基金(批准号:2020JJ4597,2021JJ30733,2021JJ40558);湖南省研究生科研创新项目(批准号:CX20210827)资助的课题。

摘　　要：利用非平衡格林函数结合密度泛函理论,研究了顺式蒽二噻吩和反式蒽二噻吩分子连接锯齿边碳化硅纳米带的自旋输运特性,并在铁磁场下观察到自旋向上和自旋向下具有同方向的自旋整流特性.在铁磁场下,边缘碳原子或者硅原子双氢原子钝化可以改变锯齿边碳化硅纳米带的本征金属性,使其转变为半导体.顺式蒽二噻吩器件和反式蒽二噻吩器件的自旋向上电流-电压特性可以呈现显著的自旋整流效应,相应的最大自旋整流比分别接近10^(11)和10^(10).此外,由于自旋向上和自旋向下电流值之间的巨大差异,两个器件的电流-电压特性都在正偏压区域呈现出完美的自旋过滤行为.以上发现对未来设计自旋功能分子器件具有重要意义.Using non-equilibrium Greens function combined with density functional theory,we investigate the spinresolved transport properties of the zigzag SiC nanoribbon(zSiCNR)connecting anthradithiophene(ADT)molecules and obtain the giant spin current rectification in the presence of a ferromagnetic field.The dualhydrogenation on edge C atoms or Si atoms can change the initial metallicity of the pristine zSiCNR with the edge mono-hydrogenation into semiconductivity in the presence of a ferromagnetic field.The up-spin currentvoltage characteristic of the cis-ADT device and the trans-ADT device can present the significant rectification,and the corresponding giant spin current rectification ratios are close to 10^(11)and 10^(10)respectively.In addition,the current-volt age characteristics of two devices both perform a perfect spin filtering behavior in the positive bias region due to the huge difference between the up-spin current value and the down-spin current value.These findings are of great significance in the functional applications of spin-resolved molecular devices in the future.

关 键 词：碳化硅纳米带 自旋输运 自旋整流 自旋过滤 

分 类 号：O469[理学—凝聚态物理]