LUMINESCENCE AND LIFETIMES OF Pr~(3+) EXCITED STATES IN KLa_(1-x)Pr_x(MoO_4)_2 AND KLa_(1-x)Pr_x(WO_4)_2 CRYSTALS

摘要

Single crystals of double molybdates and tungstates of the formula KLa_(1-x)Pr_x(MO_4)_2 (M = Mo, W) with a concentration of Pr~(3+) ions ranging from x = 0.1 to x = 0.005 have been prepared. Their electronic absorption and emission spectra have been measured and discussed as well as related to their crystal structures. Both the multiphonon relaxation and cross relaxation contribute to the decay of the ~3P_0 level of Pr~(3+) in these two matrices.