Light emission mechanism of Lu2(SiO4)O:Ce

Two types of excitation and emission spectra with ultraviolet excitation are shown at 11 K for Lu₂(SiO₄)O:Ce (LSO). Since there are two crystallographically independent lutetium sites in LSO, the existence of two Ce activation centers (two-activation-center model) is proposed. The existence of two different decay time constants of the order of tens of nanoseconds, which are characteristic for fast Ce emission, are shown at 77 K. Although the temperature dependence of the decay time and the luminescence efficiency could not be measured for the Ce2, the fact that the gamma-ray-excited emission can be reconstructed from a weighted combination of the Ce1 and Ce2 emission spectra supports the two-activation-center model for LSO