The single crystal of GdP 5O 14 :Sm 3+ ,Pr 3+ (GdPP:Sm,Pr) was grown by the hydrothermal method. The crystal belongs to the monoclinic space group P2 1/ C by X ray powder diffraction results. The dependence of Pr 3+ ion concentration in GdPP:Sm,Pr crystals on the emission intensity of 4 G 5/2 → 6 H 7/2 transitions of Sm 3+ ion and the energy transfer between Sm 3+ and Pr 3+ ions have been investigated and discussed.
The 3μm laser emission of Er 3+ ( 4 I 11/2 → 4 I 13/2 )in the YAG crystal is,in principle,selfsaturation transition,the lifetime of the upper laser level( 4 I 11/2 )being smaller than that of the olwer one( 4 I 13/2 ).The effect of the selfsaturation limit the laser output. In present work,for the first time,we report on the investigation of the utility of Pr 3+ as a sensitizer of Er 3+ ion,using Pr 3+ 4 f 2-4 f5d transition.The radiation emission from 4f5d configuration of Pr 3+ ion have been observed in the YAG∶Pr 3+ crystal.This shows that under suitable conditions this radiant process can compete successfully by non radiative decay to the 4 f configuration.Using Er 3+ Pr 3 codoped YAG it is possible to predict the position of the lowest 4 f 2-4 f5d absorption bands of Pr 3+ ion in the ultraviolet range and to present the occurrence of the energy transfer from Pr 3+ to Er 3+ ion.By xenon flash lamp pumped 2.93μm laser action in the YAG∶(Er 3+ ,Pr 3+ ) crystals was demonstrated at room temperature.
