铝原子链电子输运性质的第一性原理计算

On Electronic Transport Properties of Aluminum Atomic Chain from the First Principle

运用密度泛函理论结合非平衡格林函数方法，对5个Al原子构成的链耦合在Au（100）之间所形成的三明治结构的纳米结点的电子输运性质进行了第一性原理计算，结果得到在两极距离为2．212nm时，几何结构最稳定，此时平衡电导为0．596G0（G0=2e^2／h），电子主要通过Al链的p电子轨道进行传输；在-1．0～1．0V的电压范围内，随着正负偏压的增大，电导先减小后增大，成对称变化，而I—V曲线表现出非线性特征．

Electronic transport in Aluminum atomic chain, which is made up of 5 atoms, sandwiched be tween Au electrodes, has been investigated by means of combination of density functional theory and the non-equilibrium green＇s function method. The results have been obtained that, when the distance of two electrodes is 2. 212 nm, the geometric structure of junctions is most stable, its equilibrium conductance is 0. 596 G0 （G0 =2e^2/h）, and the transport channel is mainly comprised p electron orbit of Al chain; In the voltage range of -1.0 V-1. 0 V, with the increase of positive and negative bias, the conductance decreases first and increases after, presents symmetric change, the curve of I-V shows nonlinear characteristics.