Vacuum ultraviolet excitation of S-1(0) and P-3(0) emission of Pr3+ in Sr0.7La0.3Al11.7Mg0.3O19 and SrB4O7

The emission and excitation properties of a SrB4O7:1% Pr3+ powder sample an d a Sr0.7La0.3Al11.7Mg0.3O19:3.5% Pr3+ single crystal were investigated usi ng x-ray and synchrotron radiation. The 4f5d states of Pr3+ in these host l attices are at a higher energy than the 4f(2)[S-1(0)] state. In the hexa-al uminate this results in the successive emission of two photons. S-1(0) --> I-1(6) emission is followed by emission from the P-3(0) state. The quantum efficiency of the total P-3(0) emission is 25%. In the terra-berate the P-3 (0) emission is quenched by multiphonon relaxation to the D-1(2) state from which only weak emission is observed. In the hexa-aluminate as in the tetr a-berate, host lattice excitation does not result in efficient emission fro m the S-1(0) state. In the hexa-aluminate the excitation energy is transfer red from the host lattice preferentially to the lower-energy P-3(J) and I-1 (6) states, resulting in P-3(0) emission only.