Universal enhancement of superconductivity in 2D semiconductors by electron-electron interaction

by Francesco Mauri

Wednesday 25 Feb 2015, 15:00 → 17:00 Europe/Rome

Aula Conversi (Dipartimento di Fisica - Ed. G., Marconi)

In two-dimensional multivalley semiconductors, at low doping, even a moderate electron-electron interaction enhances the response to any perturbation inducing a valley polarization. If the valley polarization is due to the electron-phonon coupling, the electron-electron interaction results in an enhancement of the superconducting critical temperature. By performing first principles calculations beyond density functional theory, we prove that this effect accounts for the unconventional doping-dependence of the superconducting transition-temperature (Tc) and of the ma! gnetic susceptibility measured in LixZrNCl. By finding the conditions for a maximal Tc enhancement, we show how weakly-doped two-dimensional semiconductors provide a route towards high Tc superconductivity.