金属与聚乙炔环三端连接的电子输运性质

Electronic transport properties of a polyacetylene loop connected with three metallic electrodes

基于Landauer-Buttiker理论,用求解散射波函数的方法,研究了金属与环状聚乙炔链三端连接的电子输运性质.结果表明,在给定入射端的条件下,电导在正负能量上是对称的,当3个端口满足旋转对称性时,2个出射端的电导相同.电导随着导线与聚乙炔链间耦合强度的不同而呈现不同的性质,弱耦合时电导突变明显;耦合增强后,电导趋于稳定.各端的电导跟电子在该端口碳原子上的局域密度有关,随着导线与碳链间耦合强度的增大,局域密度随能量的振荡会减弱.

Based on the Landauer-Buttiker theory, it was studied electron transport properties of the three-terminal toroidal polyacetylene chain connected with metals by solving the scattering wave function. The results obtained showed that given an input terminal, the conductance was symmetrical through zero energy, if three terminals obey rotational symmetry, the conductance of the two output terminals would be equal. The conductance was showed to be dependent on the lead-polyacetylene coupling, strong oscillation appeared if the coupling was weak, if the coupling was strong, the oscillation became weak. The conductance was showed to be affected by the local density of electron of the output terminal＇s carbon atoms, the oscillation became weak if the lead-polyaeetylene coupling was strong.