Relaxation dynamics of Microcavity Polaritons in the presence of an electron gas

The dynamics of microcavity polaritons in the presence of an electron gas is investigated by means of timeresolved photoluminescence. The electrons induce a strong acceleration of the population build-up and decay, both in large wave-vector states (reservoir) and at the center of the Brillouin zone. We show that the dynamic changes in the reservoir are due to a better exciton relaxation and to the formation of a thermalized trion population. The population of the polariton states close to the center of the Brillouin zone adiabatically follows the reservoir population. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)