High pressure and time resolved luminescence spectra of Gd 3Ga 5O 12:Pr 3+ crystal

Abstract

Luminescence spectra and time resolved luminescence spectra of GGG crystal doped with Pr 3+ 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 Pr 3+ 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 3P 0 state was single-exponential and diminished with pressure from 23 μs at ambient pressure to 6.5 μs at 165 kbar. Luminescence decay related to transition form 1D 2 state was two-exponential with longer decay equal to 162 μs at ambient pressure and 120 μs at 165 kbar. We discussed effect of pressure on the 1D 2 → 3H 4 luminescence and emission from 3P 0 state in the context of non-radiative processes that depopulate the 3P 0 and populate the 1D 2 state, considering mainly multiphonon relaxation processes and depopulation via the praseodymium trapped exciton state.