On the Effect of Electron-Phonon Interaction Parameters on the Performance of Carbon Nanotube Based Transistors

Exceptional electronic and mechanical properties together with nanoscale diameter make carbon nanotubes (CNTs) promising candidates for nanoscale transistors. Semiconducting CNTs can be used as a channel for field-effect transistors (FETs), and metallic CNTs can serve as interconnect wires. In short devices carrier transport through the device is nearly ballistic [1]. The non-equilibrium Green’s function (NEGF) method has been successfully utilized to investigate the characteristics of nanoscale Silicon transistors [2], carbon nanotube (CNT) based transistors [3, 4], and molecular devices [5]. In this work we employ the NEGF formalism to study in detail quantum transport in CNT based transistors. Non-equilibrium statistical ensemble averages of the single particle correlation operator can be calculated using the NEGF formalism. Four types of Green’s functions are defined: G deal with the dynamics of carriers and G with the statistics of carriers. For a steady state problem the Green’s functions can be written as [6]: