Modeling Current Transport in Carbon Nanotube Transistors

Carbon nanotubes (CNTs) have been studied in recent years due to their exceptional electronic, opto-electronic, and mechanical properties. To explore the physics of carbon nanotube field-effect transistors (CNT-FETs) self-consistent quantum mechanical simulations have been performed. Both the electron-photon and electron-phonon interactions in CNT-FETs have been analyzed numerically, employing the non-equilibrium Green's function formalism. The numerical challenges for the analysis of carbon nanotube based photo-detectors have been investigated. The results indicate the non-locality of electron-photon interaction. For accurate analysis it is essential to include many off-diagonals of the electron-photon self-energy. Electron-phonon interaction parameters, such as electron-phonon coupling strength and phonon energy, strongly depend on the chirality and the diameter of the carbon nanotube. The steady-state and the dynamic response of carbon nanotube based transistors have been studied for a wide range of electron-phonon interaction parameters.