The impurity-induced luminescence of RbMnF3

The impurity-induced luminescence of RbMnF₃ has been studied in the temperature range, 4–120 K. Multimagnon sidebands of impurity-induced Mn²⁺ emission lines have been detected spanning the spectral range, 5515–5960 Å. The broad emission bands, which peak at 5750 Å and 6440 Å, have been attributed to phonon-assisted transitions from two impurity-induced Mn²⁺ traps of different depths. Pulsed luminescence measurements indicate that the quenching of the shallow trap emission is by a thermal activation to the E1 exciton level whereas the quenching of the deeper trap emission is by a multiple phonon decay. The coupling between Mn²⁺ ions is strong enough to support a detectable transfer of excitation between these two traps.The results of this research also include the observation in absorption of the E1 exciton line and its 1-magnon and possible 2-magnon sidebands.