Температурный сдвиг бесфононных f-f-линий люминесценции Er-=SUP=-3+-=/SUP=- в квантовом параэлектрике KTaO-=SUB=-3-=/SUB=-

Abstract

Abstract In KTaO_3:Er crystals, we observed a temperature shift, unusual for rare earth impurities, for narrow zero-phonon luminescence lines, due to the ^4 S _3/2 → ^4 I _13/2, ^4 F _9/2 → ^4 I _15/2, and ^4 S _3/2 → ^4 I _15/2 transitions in Er^3+ impurity ions. The magnitude of the shifts turned out to be comparable with the large shifts of the R lines of the Cr^3+ luminescence in SrTiO_3:Cr and KTaO_3:Cr crystals, that is, substantially larger than that for the three-charged rare earth ions usually observed in the f – f luminescence spectra in ionic crystals.