The effect of pressure on energy transfer in Cr3+:Tm3+:YAG

Abstract The effect of pressure on energy transfer in Cr3+:Tm3+:YAG has been considered. We find that pressure increases the separation in energy of the 4T2 and 2E levels of Cr3+ and that this increase leads to both an increase in Cr3+ → Tm3+ energy transfer efficiency and a decrease in Cr3+ → Tm3+ energy transfer rate. We attribute the increase in transfer efficiency to a reduction in the spin-orbit coupling of the 4T2 and 2E levels with increasing pressure and the decrease in transfer rate to the elimination of the thermal population of the 4T2 level. We include a discussion of the relationship of effects of pressure and temperature on the energy transfer properties of Cr3+.