Kuz'menko O. Effects of exchange interaction in optical and magnetotransport phenomena in narrow-gap semimagnetic semicоnductors Hg(1-x-y)Cd(x)Mn(y)Te and Hg(1-x-y)Cd(x)Mn(y)Se

Object of investigation - narrow-gap semimagnetic semiconductors Hg(1-x-y)Cd(x)Mn(y)Te and Hg(1-x-y)Cd(x)Mn(y)Se. Goal of thesis - investigation by optical and magnetotransport methods of peculiarities of electronic processes under influence of exchange interaction between localized magnetic moments of manganese ions and spins of free carriers of charge. It is shown, that there exists strong electron-phonon coupling in narrow-gap Hg(1-x-y)Cd(x)Mn(y)Te being the origin of indirect exiton generation in direct semiconductor. It is clarified the role of spin-flip processes in relaxation of fotoexcited free carriers in narrow-gap Hg(1-x-y)Cd(x)Mn(y)Te. The constants of exchange interaction are determined in Hg(1-x-y)Cd(x)Mn(y)Te and Hg(1-x-y)Cd(x)Mn(y)Se semiconductors. The dependence of constants of exchange interaction on carrier concentration and energy gap of Hg(1-x-y)Cd(x)Mn(y)Se is found in the region of semimetal -semiconductor transition. It is proved an important role of doping by magnetic ions ini mprovement of structural quality and increase of lattice stability of Hg(1-x)Cd(x)Te. The results obtained can be used in development of new technologies of growth and further treatment of narrow-gap semimagnetic AIIBVI semiconductors.