  Electron-phonon(e-ph) interaction in Ca2N monolayer, the first electrene
material with two-dimensional(2D) electron gas floating in free space, is
expected to be very weak and such a character can be used to design
weak-scattering transport channels. Therefore, it is highly desirable to
quantitatively evaluate the carrier mobility of electrene. In this study, e-ph
interaction in Ca2N monolayer is investigated using a precise Wannier
interpolation-based first principles technique. The calculated e-ph coupling
matrix elements of Ca2N monolayer are indeed small compared to other 2D
materials such as graphene, which leads to an intrinsic mobility of 189
cm2V-1s-1, much higher than those of conventional metals. Other factors
affecting mobility are discussed in a comparison with graphene. It is predicted
that, based on a momentum mismatch mechanism, mobility of Ca2N monolayer can be
increased further to above 3000 cm2V-1s-1 via hole doping. Our results confirm
that Ca2N electrene is a promising electronic material.
