An efficient method for calculating quasiparticle energies in semiconductors

We present a method for the efficient calculation of the electronic structure of semiconductors within the GW approach. It approximately includes dynamical-screening and local-field effects, previously disregarded in simplified GW approaches, without increasing the computational effort. Such effects substantially affect the gap corrections. We find quasiparticle shifts in good agreement with the complete GW calculations or experiment for Si, AlAs, GaAs and ZnSe.