Eur. Phys. J. B (2016) 89: 187
https://doi.org/10.1140/epjb/e2016-70106-7

Regular Article

Mode-detailed analysis of transmission based directly on Green’s functions

Zhejiang Institute of Modern Physics, Zhejiang University, Hangzhou 310027, P.R. China

^a e-mail: hzzhaoxa@163.com

Received: 20 February 2016
Received in final form: 29 May 2016
Published online: 5 September 2016

Abstract

Fisher-Lee relation ${t}\mathrm{=}\mathit{i}{{\Gamma }}_{\mathit{L}}^{\mathrm{1}\mathit{/}\mathrm{2}}{G}{{\Gamma }}_{\mathit{R}}^{\mathrm{1}\mathit{/}\mathrm{2}}$ is a well-established tool to decode the mode information from Green’s function and coupling parameters. Using the Bloch eigen-modes of the leads, we show that the ${{\Gamma }}_{\mathit{L}\mathit{/}\mathit{R}}^{\mathrm{1}\mathit{/}\mathrm{2}}$term can be expressed by the Bloch eigen-mode vectors and the wave velocities which give unambiguous algorithm of ${{\Gamma }}_{\mathit{L}\mathit{/}\mathit{R}}^{\mathrm{1}\mathit{/}\mathrm{2}}$in the Fish-Lee relation. Using this approach, we present an accurate and convenient technique to analyze all transport modes and also the dominant channels of an electronic transport system in tight-binding model. We study graphene nanoribbon structures to demonstrate the typical application of our technique.