Microscopic theory of the semiconductor terahertz response

A microscopic theory for the terahertz response of excited semiconductor systems is presented. It is verified that the theory yields the correct effective-mass Drude limit. For a fully interacting incoherent system, the terahertz response is shown to be determined by the electron-hole correlations. The theory is evaluated for the example of excitonic populations in a quantum-well structure. (C) 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.