The Study on Spectral Hole Burning Rate in BaFCl0.5Br0.5: Sm2+

In Sm2+ doped alkline earth halides, hole burning process is two step photoionization of Sm2+ following electron trapping [1]. The first step is using burning laser to excite electron of Sm2+ from the ground state 7F0 to the excited energy level 5DJ. The second step is using gating laser to excite the electron from the 5DJ level to the conduction band, where the free electron will be captured either by trap or by the ionized Sm2+ ion again. The overall process depends on the factors: excitation rate, the trapping rate and the recombination rate.