Luminescence properties of CsPrP 4O 12 and RbPrP 4O 12

Abstract

Single crystals of CsPrP 4O 12 and RbPrP 4O 12 cyclotetraphosphates have been grown using the flux method. Selective excitations in the Pr 3+ (4f 2) 3P 0 and 3P 2 levels using an excimer-pumped dye laser mainly result in intense line emissions in both materials. Although originating from transitions within the Pr 3+ 4f 2 ground configuration, these emissions have very short decay times, of the order of 50 ns. Both compounds also exhibit intense ultraviolet band emissions in the 200–300 nm spectral range when using either a xenon lamp or an X-ray source for optical excitation. The decays of these emissions under pulsed X-ray excitation were measured using the start–stop technique. They exhibit a main fast component (decay time τ f) and a minor slower one (decay time τ s), the decay times of which are τ f≅9 and 5 ns, τ s≅30 and 20 ns, in the Cs and Rb compounds, respectively.