Time-resolved photoluminescence (PL) and optical pump-probe experiments wer
e carried out in Cd1-xMnxTe/ZnTe multiple quantum wells to study the dynami
cs of the excitonic magnetic polaron in this material. In the pump-probe da
ta, three signals were detected. The main signal is negative and monitors t
he energy relaxation of the excitons created by the pump pulse. The other t
wo pump-probe signals are positive and their intensity grows while the exci
tons created by the pump pulse recombine. The low-energy positive pump-prob
e signal is found to track the average Mn spin polarization in the sample.
Instead, the high-energy positive peak indicates the enhancement of the den
sity of states due to correlation effects. (C) 2000 Published by Elsevier S
cience B.V. All rights reserved.