中国物理B ›› 2011, Vol. 20 ›› Issue (12): 127304-127304.doi: 10.1088/1674-1056/20/12/127304
• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇 下一篇
张广平, 胡贵超, 李宗良, 王传奎
Zhang Guang-Ping(张广平), Hu Gui-Chao(胡贵超), Li Zong-Liang(李宗良), and Wang Chuan-Kui(王传奎)†
摘要: The transport properties of a conjugated dipyrimidinyl-diphenyl diblock oligomer sandwiched between two gold electrodes, as recently reported by [Díez-Pérez et al. Nature Chem. 1 635 (2009)], are theoretically investigated using the fully self-consistent nonequilibrium Green's function method combined with density functional theory. Two kinds of symmetrical anchoring geometries are considered. Calculated current-voltage curves show that the contact structure has a strong effect on the rectification behaviour of the molecular diode. For the equilateral triangle configuration, pronounced rectification behaviour comparable to the experimental measurement is revealed, and the theoretical analysis indicates that the observed rectification characteristic results from the asymmetric shift of the perturbed molecular energy levels under bias voltage. While for the tetrahedron configuration, both rectification and negative differential conductivity behaviours are observed. The calculated results further prove the close dependence of the transporting characteristics of molecular junctions on contact configuration.
中图分类号: (Rectification)