Development of Nd-doped solid-state laser materials for 944 nm operation

We have grown neodymium-doped mixed apatite crystals [(Sr/sub 1-x/Ba/sub x/)/sub 5/(PO/sub 4/)/sub 3/F, Sr/sub 5/(P/sub 1-x/V/sub x/O/sub 4/)/sub 3/F, and Ba/sub 5/(P/sub 1-x/V/sub x/O/sub 4/)/sub 3/F] and spectroscopically studied them as potential gain media for a laser source for atmospheric water sensing operating at 944.11 nm. We conclude that an appropriate apatite host material for a 944.11 nm laser should be a mixture of Sr/sub 5/(PO/sub 4/)/sub 3/F. With a small fraction of Ba/sub 5/(PO/sub 4/)/sub 3/F. Precise wavelength tuning around 944.11 nm can be accomplished by varying the host composition, temperature, and threshold population inversion. In apatite crystals of mixed composition, the amplified spontaneous emission (ASE) loss at 1.06 /spl mu/m is predicted to be significantly smaller than that in the end members.