Eur. Phys. J. D (2014) 68: 10
https://doi.org/10.1140/epjd/e2013-40557-7

Regular Article

First principles calculation on quantum transport of Au-Si₃-Au nanoscale junction

¹ Key Laboratory of High Energy Density Physics and Technology of Ministry of Education, College of Physical Science and Technology, Sichuan University, Chengdu 610064, P.R. China
² College of Physics and Electronic Engineering, Yibin University, Yibin 644000, P.R. China
³ International Centre for Materials Physics, Chinese Academy of Sciences, Shenyang 110016, P.R. China

^a e-mail: ycheng@scu.edu.cn

Received: 7 September 2013
Received in final form: 21 October 2013
Published online: 23 January 2014

Abstract

We comparatively investigate the effect of contact geometry of Si₃ cluster sandwiched between Au (100) electrodes on electron transport, using density functional theory combined with non-equilibrium Green’s function. We simulate the Au-Si₃-Au junctions breaking process in four anchoring configurations, obtain the cohesion energy and conductance of junctions as a function of distance d_z, compare the change trend of conductance with the net charge transfer of scattering region, and calculate the current-voltage characteristic of junctions at equilibrium position. Our results show that the conductance is sensitive to the coupling morphology and the variation of the two contact distances. It is found that all junctions in equilibrium position have large conductance, the curves of I-V show linear characteristic, the cohesion energy and conductance of junctions in hollow-hollow configuration is the largest.