No abstract

The energy of excitons A, B, and C of Cd, -,Fe,S (x < 0.02) is studied as a function of Fe concentration at T = 10 K in the absence of a magnetic field. The observed band bending effect (largest for exciton A) is attributed to the s, p-d exchange interaction correction resulting from the exchange disorder.A particular class of mixed crystals is formed by the so-called diluted magnetic semiconductors (DMS, see e.g.[7]), in which nonmagnetic cations A are substituted by magnetic ions (typically transition metal ions, such as Mn, Fe, or Co). For these materials the s, p-d exchange interaction between band electrons and magnetic ions strongly modifies the random chemical potential and consequently the bowing effects. The bowing of the energy gap was observed for CdMnS [S], ZnMnSe [9, lo], and ZnMnTe [ll]. However, ') Chung Li 32023,

The valence band crystal field and spin-orbit splitting in hexagonal diluted magnetic semiconductors based on CdSe and CdS is studied. It is found that the crystal field splitting is practically magnetic ion independent for CdSe based crystals, whereas in the case of CdS based samples a strong influence of magnetic ion substitution on crystal field splitting is observed.