High pressure and time resolved luminescence spectra of Gd3Ga5O12:Pr3+ crystal

Luminescence spectra and time resolved luminescence spectra of GGG crystal doped with Pr3+ were measured at high hydrostatic pressure from ambient to 220 kbar. Effect of pressure results in the red shift of all luminescence lines related to Pr3+ ion emission equals from -0.32 to -1.02 cm(-1)/kbar and in the diminishing of the luminescence lifetimes. The luminescence decay related to emission from P-3(0) state was single-exponential and diminished with pressure from 23 mu s at ambient pressure to 6.5 mu s at 165 kbar. Luminescence decay related to transition form D-1(2) state was two-exponential with longer decay equal to 162 mu s at ambient pressure and 120 mu s at 165 kbar. We discussed effect of pressure on the D-1(2) -> H-3(4) luminescence and emission from P-3(0) state in the context of non-radiative processes that depopulate the P-3(0) and populate the D-1(2) state, considering mainly multiphonon relaxation processes and depopulation via the praseodymium trapped exciton state. (C) 2011 Elsevier B.V. All rights reserved.