Temperature properties of intracenter luminescence of Mn$^{2+}$ ions in diluted magnetic semiconductors and related heterostructures

The intracenter luminescence intensity of Mn$^{2+}$ ions in II–VI diluted magnetic semiconductors weakly varies in the temperature range of 5–60 K, but a further increase in temperature leads to a rapid quenching of luminescence. There is an opinion that a drastic change in the temperature dependence of the intracenter luminescence of Mn$^{2+}$ at about 60 K is associated with distortion of an anionic tetrahedron whose center is occupied by the manganese ion. In this work, the temperature and kinetic properties of the intracenter luminescence of Mn$^{2+}$ have been studied at different levels of optical excitation in bulk diluted magnetic semiconductor crystals and the related quantum-well structures. It has been found that quenching of the intracenter luminescence of Mn$^{2+}$ is determined by a cooperative process (up-conversion), the efficiency of which increases with an acceleration of migration and an increase in the density of excited Mn$^{2+}$ ions.