Optical and electron paramagnetic resonance studies on radiation defects in Mn-activated RbCdF₃

The photoluminescence of Mn-activated RbCdF₃ shows a Mn ²⁺ emission band at 560 nm; the corresponding excitation bands are between 240 and 520 nm. After X-irradiation an increased Mn²⁺ emission can be observed and the excitation spectrum shows an additional broad intense band at 300 nm. Upon excitation at 300 nm the intensity of the Mn ²⁺ emission decreases, whereas excitation at 240 nm leads to an increase in the PL intensity. Electron paramagnetic resonance shows that the number of Mn²⁺ ions is reduced upon X-irradiation; the original Mn²⁺ level can be restored upon optical bleaching.