Doped silicene: Evidence of a wide stability range

The effects of doping on the lattice structure, electronic structure, phonon spectrum, and electron-phonon coupling of low-buckling silicene are studied by first-principles calculations. Although the lattice is found to be very sensitive to the carrier concentration, it is stable in a wide doping range. The frequencies of the E-2g-Gamma and A'-K Raman modes can be used to probe the carrier concentration. In addition, the phonon dispersion displays Kohn anomalies at the Gamma and K points which are reduced by doping. This implies that the electron-phonon coupling cannot be neglected in field-effect transistor applications. Copyright (C) EPLA, 2011