Luminescence study of the f-f transition of Pr 3+ 1 D 2 and 3 P 0 states in KYF 4 crystals and powders

KYF 4 :Pr 3+ was prepared in the two forms of single crystal and polycrystalline powder. The visible photoluminescence properties of KYF 4 :Pr 3+ single crystal and powder have been comparatively investigated, and the special attentions were paid to the luminescence in the red region from the f-f transition of Pr3+ 3P0 and 1D2 states. We used two different pump sources of an Argon-ion laser tuned to a wavelength of 457.9 nm, 445 nm and a blue GaN laser diode emitting at 445 nm, exciting the 3P1 and 3P2 states of Pr3+ ion, respectively. The observed strong and sharp emission line at 594.6 nm for the KYF4:Pr3+ powder and crystal should be ascribed to 3P0-3H6 transition of Pr3+3+, and an …