Electrical and Thermal Non-linear Transport in Metallic Carbon Nanotubes
The interpretation of the non-linear I-V characteristics of metallic single wall carbon nanotubes under electric stress has been particularly puzzling because the role played by Joule heating remains an open question. We have developed a self-consistent electron transport model, which considers local lattice heating in metallic single wall carbon nanotubes. The model is based on the solution of the Boltzmann equation in the presence of electron-(optic) phonon scattering, in which heat production/dissipation is determined self-consistently with the local temperature in the nanotube. In addition, our model takes into account heat diffusion through the nanotubes support. Not only does our model reproduce the features of the IV characteristics as a function of tube length (fig.1), but also predicts the electrical breakdown of the nanotube. It is the first comprehensive computational model treating electric and thermal transport on equal footing, and as such constitutes an important milestone toward a complete transport theory of CN and its application in electronic and thermal devices.
Fig.1: I-V Characteristics of several CN nanotube of different lengths obtained by the self-consistent electronic-thermal model. Solid: Theory; dots: Experimental data (after Javey et al. PRL 2003). Inset: Peak temperatures in the middle of the CN as a function of the current for the different CN lengths