The one-electron excitation spectrum of the prototype semiconductor Si has been obtained from a first-principles calculation of the spectral-weight function $A(q\to ,\omega )$ of the interacting one-electron Green’s function. The Dyson equation has been solved with the self-energy operator obtained in the $\mathrm{GW}$ approximation, where the bare propagator $G$ and the ω-dependent screening matrix $W,$ without (random-phase approximation) and with (time-dependent local density approximation) vertex corrections, have been computed within Kohn-Sham–local-density-approximation theory. Positions of quasiparticle peaks (i.e., the “band structure”), their lifetimes, and satellite (plasmaron) spectral structures are extracted in a broad energy range.

• Received 24 June 1997

DOI:https://doi.org/10.1103/PhysRevB.56.10228