Quantum-confined Stark effects in CdS1-xSex quantum dots.

Quantum-confined Stark eff'ects (QCSE's) on exciton-decay dynamics in CdSo 3iSeo 69 semiconductor quantum dots (QD's) embedded in a glass matrix have been studied by time-resolved photoluminescence emission spectroscopy under different electric fields up to 2. 5 X 10 V/cm. Under both conditions, in the absence or in the presence of an applied electric field, the exciton luminescence decay in QD's is found to follow the stretched exponential function I(t) =Ioexp( —Ate). The decay rate A and exponent p are found to vary linearly with the applied electric field, which can be accounted for by the field-induced reduction of the confined electron and hole wave-function overlap in QD's. The QCSE observed in the QD's is weaker than those observed in semiconductor quantum-well structures.