γ-石墨炔基分子磁隧道结的输运性能  

Transport Properties ofγ-Graphyne-Based Molecular Magnetic Tunnel Junctions

作　　者：李瑾 邸茂云 刘旭光[3] 杨致[4] Li Jin;Di Maoyun;Liu Xuguang;Yang Zhi(College of Chemical Engineering and Technology,Taiyuan University of Science and Technology,Taiyuan 030024,China;College of Materials Science and Engineering,Taiyuan University of Science and Technology,Taiyuan 030024,China;College of Materials Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,China;College of Physics,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]太原科技大学.化学工程与技术学院,太原030024 [2]太原科技大学材料科学与工程学院,太原030024 [3]太原理工大学材料科学与工程学院,太原030024 [4]太原理工大学物理学院,太原030024

出　　处：《微纳电子技术》2023年第12期1953-1962,共10页Micronanoelectronic Technology

基　　金：山西省应用基础研究计划青年项目(202203021212324,202203021222202);山西省优秀来晋博士科研启动金(20232054,20232053);山西省高等学校科技创新项目(2022L304);太原科技大学校级博士科研启动基金项目(20222037,20222049)。

摘　　要：对γ-石墨炔进行剪切可以得到零维γ-石墨炔纳米点(γ-GYND),采用密度泛函理论和非平衡格林函数相结合的方法,利用γ-石墨炔纳米点和锯齿型石墨烯纳米带理论设计了三种连接方式的分子磁隧道结(MMTJ),并研究了这三种磁隧道结的输运性能。研究结果表明,γ-石墨炔纳米点和锯齿型石墨烯纳米带连接方式不同,所构建的几种分子磁隧道结输运性能不同,即随着电压的增加,三种分子磁隧道结中电流的变化趋势不同,虽然都观察到了明显的自旋过滤效应和巨磁阻效应,但自旋极化率和隧穿磁阻不同,其中隧穿磁阻最大可达10^(9)%量级,这一数值远高于传统磁隧道结,实验上这一数值只有18%。以上结果表明,γ-石墨炔纳米点和锯齿型石墨烯纳米带所组成的磁隧道结可以应用于自旋电子器件,也可用于通过改变电压或磁场信号得到相应的电流从而起到信息传递作用的分子传感器。By cuttingγ-graphyne,0Dγ-graphyne nanodots(γ-GYNDs)can be obtained.By combining density functional theory with non-equilibrium Green's function,molecular magnetic tunnel junctions(MMTJs)with three different connection ways were designed withγ-graphyne nanodots and zigzag graphene nanoribbon theories,and the transport properties of three kinds of magnetic tunnel junctions were investigated.The research results show that the connection ways ofγ-graphyne nanodots and zigzag graphene nanoribbons are different,therefore the constructed MMTJs have different transport properties.It indicates that with the increase of the voltage,the variation trends of currents in three MMTJs are different.The obvious spin-filtering effect and giant magnetoresistance effect can be observed,while spin polarizability and tunneling magnetic resistance are different,the maximum tunneling magnetic resistance can be 10^(9)%order of magnitudes,which is much higher than that of the traditional magnetic tunnel junction,it is only 18%obtained in the experiment.The above results indicate that the magnetic tunnel junctions composed ofγ-graphyne nanodots and zigzag graphene nanoribbons can be applied to spin electronic devices and molecular sensors that can transmit information by changing the voltage or magnetic field signal to obtain the corresponding current.

关 键 词：分子磁隧道结(MMTJ) 石墨炔纳米点 石墨烯纳米带(GNR) 自旋过滤效应 隧穿磁阻效应 

分 类 号：O471.1[理学—半导体物理]