Carrier transport in layered nanolaminated carbides

Abstract

This paper summarizes the ab-initio electronic and phonon band structures and the temperature-dependent carrier transport in layered Ti2AlC. It is found that the cylindrical Fermi surface is the origin of the anisotropic carrier effective mass (infinite effective mass along the c axis), which leads to a strong anisotropic (insulator along the c axis and metallic along the layer) carrier transport in these films. Using electronic and phonon band structure calculations, we have developed an analytical model for the carrier-phonon interaction and the in-plane carrier conductivity originating from the strong inter-valley (s → d) scattering in Ti2AlC. The density functional theory is used to calculate the average deformation potential corresponding to the acoustic phonon vibrations. The calculated deformation potential is in good agreement with the extracted deformation potential from the transport data available in the literature. The extracted deformation potential will be useful for predicting the transport quantities of these metals at elevated temperatures.