Exploration of the thermal shift parameters for the six luminescence peaks in Nd3+-doped YAlO3

Abstract

In this paper, we analysis the thermal shifts of six luminescence peaks (R1 → Y2,3,5, R1 → Z3, R2 → Y1, R2 → Z3) in Nd3+-doped YAlO3 crystal with a full expression including both the static effect (characterized by the static parameter A) from lattice thermal expansion and the dynamic effect (characterized by the electron-phonon coupling parameter α′) originating from the electron-phonon interaction. The static effect is evaluated from the pressure shift of the spectral peak. The two thermal shift parameters A and α′ for these peaks are attained by means of an approximate treatment on the full expression. The results indicate that differing from the previous opinion, even in the ‘hard’ crystal YAlO3:Nd3+, the static effects to thermal shifts of most peaks are important and cannot be ignored. The estimated thermal shift parameters A and α′ for the spectral peaks of YAlO3:Nd3+ in order of magnitude are the same as those of various 4fn ions in crystals found previously and can be seen as reasonable. The cause of negative static parameters A (which were not reported previously) for some peaks is discussed.