(4,4)碳纳米管/碳化硅纳米管异质结的输运特性  

Electronic transport properties of a (4,4) carbon nanotube/silicon carbide nanotube heterojunction

作　　者：刘红霞[1] 宋久旭[1,2] 张鹤鸣[1] 

机构地区：[1]西安电子科技大学宽禁带半导体材料与器件教育部重点实验室,陕西西安710071 [2]西安石油大学电子工程学院,陕西西安710065

出　　处：《西安电子科技大学学报》2010年第3期520-523,共4页Journal of Xidian University

基　　金：国家部委预研基金资助项目(51308040203)

摘　　要：建立了(4,4)碳纳米管/碳化硅纳米管异质结的模型,采用非平衡格林函数法计算了该异质结的输运特性.从异质结的分子投影自洽哈密顿量的本征轨道,可以看出最高占据分子轨道和最低空轨道均位于碳纳米管侧,其能带间隙约为0.48 eV;从其伏安特性可以看出,在正负偏压下开启电压为+2.0 V和-1.6 V.The transport properties of the nanotube heterojunctions are the basis for the studies of their working mechanism, which is important for the theoretical study and the practical application. First, atwo-probe model for a （4, 4） carbon nanotube （CNT）/silicon carbide nanotube （SiCNT） heterojunction is established. The transport properties of the heterojunction is realized with the nonequilibrium Green＇s function （NEGF）. From the orbitals of the molecule projected self-consistent Hamiltonian, we can see that the highest occupied molecular orbital （HOMO） and the lowest unoccupied molecular orbital （LUMO） concentrate mainly on the CNT section and that the band gap of the heterojunction is about 0.48 eV. The turn-on voltages of the heterojunction under the positive and negative voltage are ＋2. 0 V and -1.6 V, which can be achieved from its voltage-current characteristic.

关 键 词：碳纳米管 碳化硅纳米管 异质结 输运特性 非平衡格林函数 

分 类 号：TN304[电子电信—物理电子学]