Thermal Quenching of Tb+3, Tm+3, Pr+3, and Dy+3 4<i>fn</i> Emitting States in La2 O2 S

Abstract

Thermal quenchings of +3 rare-earth line emissions were measured for excitation into the 4fn emitting states. These quenchings differ from corresponding quenchings reported by Wickersheim and Buchanan for band-gap excitation. For Tb+3, Tm+3, and possible Pr+3, the quenchings from the 4fn emitting states are attributed, as in the previously well-established Eu+3 case, to thermally promoted crossovers to Franck-Condon-shifted states.