Quasiparticle and excitonic effects in the optical spectra of diamond, SiC, Si, GaP, GaAs, InP, and AlN

We demonstrate the potential of recently developed electronic‐structure methods for the calculation of the optical properties of solids. As prototypical examples semiconductors crystallizing in diamond or zinc‐blende structure are studied. The many‐body effects are fully taken into account by a solution of the combined Dyson and Bethe‐Salpeter equations. We show that an initial‐value formulation of the polarization function allows for an efficient numerical calculation of the optical susceptibility. The effect of the renormalization of electrons and holes to quasiparticles is shown for both the band structure and the optical spectrum. In addition, excitonic effects are identified to remarkably influence the optical absorption. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)