INTERPARTICLE INTERACTION IN SPIN-ALIGNED AND SPIN-DEGENERATE EXCITONSYSTEMS AND MAGNETOPLASMAS IN II-VI QUANTUM-WELLS

Magnetoluminescence studies of highly excited undoped CdTe/Cd0.88Mn0.1 2Te and Cd0.97Mn0.03Te/Cd0.75Mg0.25Te quantum wells (QW's) have been c arried out in magnetic fields up to 14 T at 4.2 K. Qualitatively diffe rent excitonic systems, spin aligned in (Cd,Mn)Te QW and spin depolari zed in CdTe QW, have been generated. The interaction of spin-aligned e xcitons are found to be weakly repulsive. In contrast, an additional w ell pronounced emission line M has been found to appear at approximate ly 5 meV below the excitonic line in the spectra of the spin-degenerat e system. This line is assigned to the emission of excitonic molecules consisting of excitons with different spins. Finally, we have shown t hat the renormalization of Landau-level transitions in dense electron- hole magnetoplasmas with several occupied Landau levels depends on the ir spin state, it is markedly weaker in the spin-polarized plasmas.