中国物理B ›› 2011, Vol. 20 ›› Issue (9): 97201-097201.doi: 10.1088/1674-1056/20/9/097201

• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇    下一篇

An easy and efficient way to treat Green's function for nano-devices with arbitrary shapes and multi-terminal configurations

杨谋, 冉先进, 崔岩, 王瑞强   

  1. Laboratory of Quantum Information Technology, School of Physics and Telecommunication Engineering, South China Normal University, Guangzhou 510006, China
  • 收稿日期:2011-03-03 修回日期:2011-04-24 出版日期:2011-09-15 发布日期:2011-09-15

An easy and efficient way to treat Green's function for nano-devices with arbitrary shapes and multi-terminal configurations

Yang Mou(杨谋), Ran Xian-Jian(冉先进), Cui Yan(崔岩) and Wang Rui-Qiang(王瑞强)   

  1. Laboratory of Quantum Information Technology, School of Physics and Telecommunication Engineering, South China Normal University, Guangzhou 510006, China
  • Received:2011-03-03 Revised:2011-04-24 Online:2011-09-15 Published:2011-09-15

摘要: The efficiency of the calculation of Green's function (GF) for nano-devices is very important because the calculation is often needed to be repeated countlessly. We present a set of efficient algorithms for the numerical calculation of GF for devices with arbitrary shapes and multi-terminal configurations. These algorithms can be used to calculate the specified blocks related to the transmission, the diagonals needed by the local density of states calculation, and the full matrix of GF, to meet different calculation levels. In addition, the algorithms for the non-equilibrium occupation and current flow are also given. All these algorithms are described using the basic theory of GF, based on a new partition strategy of the computational area. We apply these algorithms to the tight-binding graphene lattice to manifest their stability and efficiency. We also discuss the physics of the calculation results.

Abstract: The efficiency of the calculation of Green's function (GF) for nano-devices is very important because the calculation is often needed to be repeated countlessly. We present a set of efficient algorithms for the numerical calculation of GF for devices with arbitrary shapes and multi-terminal configurations. These algorithms can be used to calculate the specified blocks related to the transmission, the diagonals needed by the local density of states calculation, and the full matrix of GF, to meet different calculation levels. In addition, the algorithms for the non-equilibrium occupation and current flow are also given. All these algorithms are described using the basic theory of GF, based on a new partition strategy of the computational area. We apply these algorithms to the tight-binding graphene lattice to manifest their stability and efficiency. We also discuss the physics of the calculation results.

Key words: Green's function, tight-binding, numerical calculation

中图分类号:  (General formulation of transport theory)

  • 72.10.Bg
73.23.-b (Electronic transport in mesoscopic systems) 72.80.Vp (Electronic transport in graphene)