We present a comparative study of two self-assembled quantum dot (QD) systems based on II-VI compounds: CdTe/ZnTe and CdSe/ZnSe. Using magneto-optical techniques we investigated a large population of individual QDs. The systematic photoluminescence studies of emission lines related to the recombination of neutral exciton X, biexciton XX, and singly charged excitons (X$^+$, X$^-$) allowed us to determine average parameters describing CdTe QDs (CdSe QDs): X-XX transition energy difference 12 meV (24 meV); fine-structure splitting $delta_{1}=$0.14 meV ($delta_{1}=$0.47 meV); $g$-factor $g=$2.12 ($g=$1.71); diamagnetic shift $gamma=$2.5 $mu$eV$/$T$^{2}$ ($gamma=$1.3 $mu$eV$/$T$^{2}$). We find also statistically significant correlations between various parameters describing internal structure of excitonic complexes.
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