摘要
利用紧束缚近似模型、递归格林函数方法和交流输运理论,研究金属电极石墨烯纳米系统中的电子交流输运性质。研究结果表明,金属电极石墨烯纳米系统中的界面散射导致总体的直流电导变小。在狄拉克点附近,中心锯齿型石墨烯条带部分的长度变化造成系统的共振和反共振效应,并对外加电压表现出类似电感(inductive-like)和电容(capacitive)的响应。电子局域态密度的分布表明,共振态电子在石墨烯纳米条带中呈边缘态分布,有利于系统的电子传导。反共振态电子的局域态密度小,系统不存在边缘态,从而抑制电子传导。
The properties of electronic AC transport of normal-metal contacted grpalaene nano-system were investigated by employing the tight-binding approximation, Green＇s function method and AC transport theory. The results show that the DC conductances are suppressed due to the interface scattering in the normal-metal contacted graphene r^no-system. The variation of the length of center graphene nanoribbon gives rise to the resonance and anti-resonance effect near the Dimc point, and induces inductive-like and capacitive responses to applied voltage. According to the results of distribution of LDOS, the resonant electrons locate at the edge of the center graphene structure, which is benefit to the conductance. While there is no edge effect of the anti-resonant electrons, with a small value of LDOS and a suppression of conductance.
出处
《电子元件与材料》
CAS
CSCD
2015年第12期36-40,共5页
Electronic Components And Materials
基金
国家自然科学基金资助项目(No.11447206
11504137)
江苏省自然科学基金资助项目(No.BK20140131)
关键词
电子输运
格林函数方法
紧束缚近似
金属电极
石墨烯
纳米器件
electronic transport
~reen＇s function method
tight binding approximation
normal-metal electrodes
graphene
nano-device
