Interference effects in electronic transport through metallic single-wall carbon nanotubes
Interference effects in electronic transport through metallic single-wall carbon nanotubes
复制标题
金属单壁碳纳米管电子传输的干扰效应
DOI：
--
复制
发表时间：
2002
期刊：
影响因子：
--
通讯作者：
J. Barnaś
中科院分区：
文献类型：
--
作者：
S. Krompiewski;J. Martinek;J. Barnaś
在Liang等人最近发表的一篇论文[Nature (London) 411, 665(2001)]中，实验表明，金属纳米管与外部电极强耦合，可以作为电子输运的相干分子波导。基于散射矩阵方法的理论分析支持了实验结果。本文采用实空间方法对这一问题进行了理论分析，使控制界面接触质量成为可能。在紧密结合模型中考虑了纳米管的电子结构。假设外部电极和中心部分（样品）由碳纳米管制成，而电极与样品之间的接触由适当的现场（对角线）和跳跃（非对角线）参数模拟。电导的计算采用格林函数技术与朗道尔形式相结合的方法。在显示电导对偏置和栅极电压的图中，我们发现了典型的金刚石结构模式，与实验观察到的相似。然而，在某些情况下，我们发现了图案中的新特征，例如双金刚石子结构。
In a recent paper Liang et al. [Nature (London) 411, 665 (2001)] showed experimentally, that metallic nanotubes, strongly coupled to external electrodes, may act as coherent molecular wave guides for electronic transport. The experimental results were supported by theoretical analysis based on the scattering matrix approach. In this paper we analyze theoretically this problem using a real-space approach, which makes it possible to control quality of interface contacts. Electronic structure of the nanotube is taken into account within the tight-binding model. External electrodes and the central part (sample) are assumed to be made of carbon nanotubes, while the contacts between electrodes and the sample are modeled by appropriate on-site (diagonal) and hopping (off-diagonal) parameters. Conductance is calculated by the Green function technique combined with the Landauer formalism. In the plots displaying conductance versus bias and gate voltages, we have found typical diamond structure patterns, similar to those observed experimentally. In certain cases, however, we have found new features in the patterns, such as a double-diamond substructure.