Correlation effects in the excitonic optical properties of semiconductors

A microscopic many-body theory for the optical and electronic properties of semiconductors is reviewed with an emphasis on the role of correlation eff ects. At the semiclassical level, the semiconductor Bloch equations include many-body effects via bandgap and field renormalization as well as correla tion contributions representing two electron-hole pair amplitudes, excitoni c populations, and coupled interband and intraband coherences. These Coulom b interaction induced carrier correlations lead to characteristic signature s in nonlinear semiconductor spectroscopy. At the fully quantum mechanical level the dominant light-matter correlations are described by coupled semic onductor Bloch and luminescence equations. Excitonic emission properties of quantum well and microcavity systems are discussed, including effects such as coherent signatures in the secondary emission and coherent control of t he emitted light.