Excited state absorption and fluorescence line narrowing studies of Cm3+ in LuPO4

Laser selective excitation, fluorescence line narrowing, and excited state absorption techniques have been used to investigate the electronic-energy-level structure of the 5f7 ion Cm3+ in the host crystal LuPO4. Crystal-field levels have been determined up to 35 700 cm−1 for the principal D2d symmetry site. Eighty levels have been assigned and fitted to a parametric Hamiltonian with an rms deviation of 28.4 cm−1. Inhomogeneous broadening of the electronic transitions and the small 9.5 cm−1 splitting of the nominally 8S7/2 ground multiplet are responsible for satellite lines reported previously. Time resolved fluorescence line narrowing was used to observe energy transfer between different subsites of the intrinsic Cm3+ center. It was found that electric-dipole interactions mediate this energy transfer.