The effect of pressure on luminescence properties of Cr3+ ions in LiSc(WO4)2 crystals-Part II: Pressure- and temperature-dependent luminescence kinetics

Luminescence kinetics of the LiSc(WO4)2 crystals doped with trivalent chromium has been investigated by high-pressure spectroscopy in the pressure range from ambient to 227 kbar, at temperatures from 20 K to room. For pressure range146-181 kbar we observed that pressure induced the structural transformation where the broad band emission related to 4T2→4A2 transition was gradually replaced by sharp R-lines emission, related to 2E→4A2 transition. We have found that both the broad band and R-line luminescence decays obtained at different pressures and temperatures are non-exponential. Distribution of the R-line luminescence decay constants has been analyzed quantitatively in the context of inhomogeneous Cr3+ sites distribution.