title: Computational study of exciton generation in suspended carbon nanotube transistors.
abstract: Optical emission from carbon nanotube transistors (CNTFETs) has recently attracted significant attention due to its potential applications. In this paper, we use a self-consistent numerical solution of the Boltzmann transport equation in the presence of both phonon and exciton scattering to present a detailed study of the operation of a partially suspended CNTFET light emitter, which has been discussed in a recent experiment. We determine the energy distribution of hot carriers in the CNTFET and, as reported in the experiment, observe localized generation of excitons near the trench-substrate junction and an exponential increase in emission intensity with a linear increase in current versus gate voltage. We further provide detailed insight into device operation and propose optimization schemes for efficient exciton generation; a deeper trench increases the generation efficiency, and use of high-k substrate oxides could lead to even larger enhancements.
authors.affiliation: Electrical and Computer Engineering, Purdue University, West Lafayette, IN 47906, USA. koswatta@purdue.edu
authors.forename: Siyuranga O
authors.initials: SO
authors.lastname: Koswatta
authors.forename: Vasili
authors.initials: V
authors.lastname: Perebeinos
authors.forename: Mark S
authors.initials: MS
authors.lastname: Lundstrom
authors.forename: Phaedon
authors.initials: P
authors.lastname: Avouris
mesh_terms: D003198:Computer Simulation; D017076:Computer-Aided Design; D008027:Light; D008956:Models, Chemical; D037742:Nanotubes, Carbon / Q000737:chemistry*; D014159:Transducers; D014173:Transistors, Electronic
chemical_list: D037742:Nanotubes, Carbon