锯齿-扶手椅-锯齿型石墨烯纳米带电子输运特性研究  

Electron transport characteristics of zigzag-armchair-zigzag graphene nanoribbons

作　　者：齐越 王俊强 朱泽华 李孟委 QI Yue;WANG Junqiang;ZHU Zehua;LI Mengwei(School of Instrument and Electronics,North University of China,Taiyuan030051,China;Academy for Advanced Interdisciplinary Research,North University of China,Taiyuan030051,China)

机构地区：[1]中北大学仪器与电子学院,山西太原030051 [2]中北大学前沿交叉科学研究院,山西太原030051

出　　处：《电子元件与材料》2022年第4期362-368,共7页Electronic Components And Materials

基　　金：国防科技173计划技术领域基金项目(2021JCJQJJ0172)。

摘　　要：基于密度泛函理论和非平衡格林函数,研究了中心散射区长度对于锯齿-扶手椅-锯齿型石墨烯纳米带(Z-A-ZGNRs)的电子输运特性的影响。结果表明:中心散射区长度对导电性能有很大的影响。散射区长度较小时,在一定区间内具有明显的负微分电阻现象,长度增加时,这种效应减弱。Z-A-ZGNRs在-2~2 V偏压下存在整流现象,散射区长度较小时,在负偏压下导电性能优于正偏压,存在反向整流现象,最大整流比为1.98;长度较大时在正偏压下导电性能优于负偏压,存在正向整流现象,最大整流比为2.54。在-1~1 eV内,散射区长度较长的能量窗内几乎无透射曲线,表明在该能量区间几乎没有电流,器件处于截止状态。该理论计算结果对石墨烯纳米器件的设计具有一定的参考价值。Based on density functional theory and non-equilibrium Green’s function,the effect of the central scattering length on the electron transport characteristics of zigzag-armchair-zigzag graphene nanoribbons(Z-A-ZGNRs)was investigated.The results show that the center scattering length has great influence on the conductivity.When the length of scattering region is small,the device is obviously negative differential resistance in a certain range.As the length increases,this effect diminishes.The conductivity of Z-A-ZGNRS is better under negative bias voltage,and the maximum reverse rectification ratio is 1.98 when the length of scattering region is short.While the length is large,the conductivity is better under the positive bias voltage,and the maximum forward rectification ratio is 2.54.In the energy range of-1-1 eV,there is almost no transmission curve in the energy window for longer central scattering region,indicating that the device has no current and is in the cutoff state.The theoretical calculation results could provide reference for the design of the graphene nanodevices.

关 键 词：石墨烯纳米带 输运性质 密度泛函理论 非平衡格林函数 中心散射区 

分 类 号：TB34[一般工业技术—材料科学与工程] TN379[电子电信—物理电子学]