串联组装双C_(60)的电子结构和输运特性

Electronic structure and transport characteristics of the inseries assembled double-C_(60)

利用第一原理密度泛函理论计算组装C_(60)形成能和电子结构,用半经典隧穿理论研究了串联C_(60)的电子输运特性.结果显示:六边形对六边形双C_(60)比边对边双C_(60)稳定;库仑阻塞与系统的结构密切相关,并且只有阴极结比阳极结窄时,才会出现库仑阻塞;低温时出现非常明显库仑台阶,温度较高时其被热效应抑制.

The formation energy and electronic structures of the series-connected C60 molecule are calculated by the ab initio density - functional theory. The I-V characteristics and tunneling effects of it are studied by electronic transport calculations with a semi classical approach. The results show that the hexagon on hexagon-double-C60is more stable and the Coulomb blockade is closely related to the structures of systems, and that the necessary condition for the Coulomb staircase to occur is that the cathode junction is narrower than that of the anode. The Coulomb staircase, evident at lower temperatures, could be suppressed by temperature elevation.