From coherently excited highly correlated states to incoherent relaxation processes in semiconductors

Recent theories of highly excited semiconductors are based on two formalism s, referring to complementary experimental conditions, the real-time nonequ ilibrium Green's function techniques and the coherently controlled truncati on of the many-particle problem. We present a novel many-particle theory co ntaining both of these methods as limiting cases. As a first example of its application, we investigate four-particle correlations in a strong magneti c field including dephasing resulting from the: growth of incoherent one-pa rticle distribution functions. Our results are the first rigorous solution concerning formation and decay of four-particle correlations in semiconduct ors. They are in excellent agreement with experimental data.