Temperature dependence of the luminescence spectra of garnet crystals doped with chromium ions

Abstract We have investigated the spectral behavior of a number of garnet crystals doped with chromium ions in a range of temperatures from 25 to 800 K. The crystals we considered are, in order of decreasing crystalline field, Y 3 Al 5 O 12 (YAG), Gd 3 Ga 5 O 12 (GGG) and Gd 3 Sc 2 Ga 3 O 12 (GSGG). By investigating their luminescence spectra, including their vibronic spectra, over a very broad range of temperatures, we attempt to obtain a fuller picture of the processes following excitation.