摘要
並列摘要
The optical properties of the self-organized type-II ZnTe/ZnSe quantum dots are studied by photoluminescence (PL) and time-resolved PL under different excitation intensities and temperatures. A blue shift of the quantum-dot peak is observed in the power-dependent PL due to the band-bending effect. The full width at half maximum (FWHM) of PL reduces firstly then broadens with increasing temperature, revealing a signature of the carrier lateral transfer. The time-resolved PL signal is well fitted by the combination of a single exponential and a stretch-exponential function, whose carrier lifetime is corresponding to τ1(shorter lifetime) and τ2(longer lifetime), separately. The carrier lifetime of τ1 decreases with increasing excitation intensity due to the increase of the overlap between electron and hole wavefunctions. On the other hand, τ2 increases with excitation intensity, resulting from the increase of the lateral carrier transfer.