Rare earth photoionization study by the resonant microwave cavity technique

Abstract Photoconductivity spectra of rare earth-doped insulating materials are measured using the resonant microwave cavity method. This technique is based on the detection of the cavity Q -factor changes induced by irradiation of the sample (inserted in the cavity) by a pulsed tunable laser. Results obtained with Lu 2 (SiO 4 )O:Ce 3+ and BaF 2 :Eu 2+ are presented and discussed. Photoionization thresholds at 400 nm (3.1 eV ) and 310 nm (4.0 eV ) are measured for Lu 2 (SiO 4 )O:Ce 3+ and BaF 2 :Eu 2+ , respectively.