摘要
采用密度泛函理论和非平衡格林函数相结合的方法对Au(100)-Si-Au(100)系统左侧对顶位、右侧对空位的纳米结点的电子输运性质进行了理论模拟计算,结果得到纳米结点的电导随电极距离(dz)增大而减小.在dz=9.72时,结点的结合能最低,结构最稳定,此时电导为1.227G0(G0=2e2/h),其电子输运通道主要是Si原子的px,py和pz轨道电子形成的最高占居轨道共振峰;在外偏压下,电流-电压曲线表现出线性特征;随着外加正负电压的增大,电导略有减小,且表现出不对称性的变化.
The transport property of silicon sandwiched between Au（100）and Au（100）is investigated with a combination of density functional theory and non-equilibrium Green＇s function method.It is found that the conductance decreases with distance increasing.When dz = 9.72 ,the structure of junctions is the most stable and the conductance is 1.227G0（G0 = 2e2/h）,which is contributed by the px,py and pz electron orbits of silicon atom.The I-V curve of junctions shows linear characteristics under the external bias vottage.With the increase of an external positive and negative voltage,the conductance decreases slightly,and presents the asymmetry change.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2013年第10期380-385,共6页
Acta Physica Sinica
基金
国家自然科学基金(批准号:11174214,11204192)资助的课题~~
关键词
硅原子
电子输运
密度泛函理论
非平衡格林函数
silicon atom
electronic transport
density functional theory
non-equilibrium Green＇s function
