We have investigated the electrical resistivity, magnetotransport, and heat capacity in several compounds of the type $M_{n+1}A{C}_n$. The temperature dependence of the electrical resistivity and the electronic contribution to the heat capacity of this family of materials are strongly influenced by electron-phonon coupling. We have extracted two independent values for the electron-phonon coupling parameter $\lambda$ from the experimental data and find consistency between the two sets. We use $\lambda$ to predict the superconducting transition temperature $T_c$ of these materials. In agreement with those predictions, ${\mathrm{Nb}}_2\mathrm{AsC}$ has a superconducting transition near $2\mathrm{K}$.

• Received 3 February 2006

DOI:https://doi.org/10.1103/PhysRevB.74.174501