Optical spectroscopy of CaMoO4:Dy3+ single crystals

CaMoO 4 single crystals doped with Dy 3+ were grown from sodium molybdate flux. Their absorption and visible emission spectra and decay curves were measured at different temperatures from 10 to 298 K. The complete energy level scheme has been deduced from the low-temperature measurements. The Judd-Ofelt parametrization scheme has been applied to the analysis of the room temperature absorption spectra. The calculated radiative lifetime of the 4 F 9/2 state is 152±5 µs, and it is in reasonable agreement with the experimental data. The decay curves measured in the 10-170 K temperature range are not exponential and obey the Inokuti-Hirayama model for energy transfer for an electric quadrupole-quadrupole interaction in the absence of diffusion among the donors. All spectral features are strongly affected by an inhomogeneous broadening connected with the `disordered crystal' character of the title compound.