Apatite laser material

Neodymium. Neodymium can be present in relatively high concentrations in fluorapatites. Gaft et al. (2001a) lists Nd analyses for several natural apatites that are higher than any other REE except Ce, and at a concentration level of about 40% of the Ce value. Nd emission is well into the IR, and it is not sensitized by most of the other REE. Hence, Nd emission is expected to be relatively independent of other impurities, and will not contribute to visible luminescence. However, Nd -doped synthetic apatites are excellent laser materials, due to several physical attributes of the Nd electronic structure in the host lattice. Detailed evaluation of the optical properties of Nd in Ba fluorapatite... 

Synthetic apatite activated by and Mn " are used as potential laser materials (Payne et al. 1994 Moncorge et al. 1994). 

Also neodymium lead chloro apatites have been synthesized and their crystals grown with the purpose of obtaining new laser materials (Grisafe and Hummel, 1970 Michel et al., 1975, Joukoff et al., 1978). They are prospective minilaser crystals (Guillot et al., 1980). The condensed phosphates have been evaluated, along with the borates, as hosts for Tb laser applications (Colak and Zwicker, 1983). 

Martin P, Chevarier A, Chevaruier N, Panczer G (1996) The French-Israeli Workshop on Apatites and Lasers, Jerusalem Martin P, Carlot G, Chevarier A, Den-Auwer C, Panczer G (1999a) J Nuclear Materials 275 268-278... 

Biomimetic nanocrystalline apatite coatings were deposited on titanium substrates by matrix-assisted pulsed laser evaporation (MAPLE), a technique with potential application in tissue engineering (Visan et al., 2014 Caricato etal., 2014). The targets were prepared from nano-sized, poorly crystalline apatite powders, analogous in composition to mineral bone. For the deposition of thin films, a KrF excimer laser source was used (A = 248 nm,rFWHM < 25 ns). Analyses of the deposited films showed that the structural and chemical nature of the nanocrystalline precursor apatite was preserved. Hence, MAPLE may be a suitable technique for the congruent transfer of a delicate material such as nanohydroxyapatite. 

Figure 25. Laser-excited luminescence in fossil fish teeth from phosphorite beds in the Senonian Mishash formation, Israel. (A) Uranyl emission at 77 K indicating uranyl aqueous complexes. (B) after annealing at 1000 K the uranyl complexes are dehydrated . (C) Same as in A but spectrum collected at 300 K. From these data it was concluded that the uranyl resides in organic material and not in the apatite structure. Modified after Gaft et al. (1996b).

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