Fluorescence Decay Dynamics of Pr³+ Ions Doped in PbWO4 Crystal

Fluorescence decay curves of the ³P₀ and ¹D₂ manifolds in Pr³⁺ doped PWO₄ crystal were measured at room temperature and the fluorescence lifetimes of both manifolds were obtained from those curves. The radiative lifetimes of the ³P₀ and ¹D₂ manifolds were calculated from the modified J-O theory without the ³H₄→³P₂ transition. The main mechanism of fluorescence quenching of the ³P₀ manifold is the non-radiative relaxation to the defect centers coming into being during the crystal growth. The dominant mechanism of fluorescence quenching of the ¹D₂ manifold is the cross-relaxation energy transfer involving the ¹G₄ and ³F₄ manifolds. The Inokuti-Hirayama model was used to analyze to the decay curve and the cross-relaxation of dipole dipole interaction was conformed.