Key role of electron-phonon interactions in the electronic conductivity ofTi3SiC2: Experiment andab initiocalculations

Abstract

The electronic conductivity anisotropy of $\mathrm{T}{\mathrm{i}}_{3}\mathrm{Si}{\mathrm{C}}_{2}$ is directly evidenced from data collected on (i) a thin film epitaxially grown on a $(11\overline{2}0)$-oriented SiC single crystal and (ii) a single crystal. Density functional theory calculations, including the linear-response approach and coupled to a Bloch-Gr\uneisen model, show that the electron-phonon interactions are mainly responsible for the observed anisotropy. Detailed analysis of the electron-phonon coupling constants allows for the rationalization of these scattering processes in terms of the $\mathrm{T}{\mathrm{i}}_{3}\mathrm{Si}{\mathrm{C}}_{2}$ nanostructure, giving insights into the possibility of modifying the electron-phonon interaction in this system by substitution effects.