Impact of exciton Zeeman splitting energy variation on the magnetoluminescence of an inhomogeneously broadened ensemble of epitaxial CdSe/(Zn,Mn)Se quantum dots

We report anomalous behavior in the circularly polarized components of photoluminescence (PL) from an ensemble of epitaxial CdSe/(Zn,Mn)Se quantum dots (QDs) subjected to a magnetic field in the Faraday geometry at 1.6 K. With increasing magnetic field, the intensity of the PL component shifting to higher energy increases, while that of the component shifting to lower energy decreases. This behavior is attributed to a QD size-dependent exciton Zeeman splitting, arising from variations in the penetration of the exciton wave function into the magnetic barrier. These variations modulate the strength of the $s$/$p\text{\ensuremath{-}}d$ exchange interaction.