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The Nd:YAG ceramics of nominal 1% and 2% Nd dopant were produced by a solid-state reaction of high-purity (4N)
nanometric oxides powders i.e. Al2O3, Y2O3 and Nd2O3. Yttrium oxide nanopowder (XRD crystallite size of 79 nm) was
produced by precipitation from water solution of high-purity hydrated nitrate, by means of ammonia hydro-carbonate. The
cold isostatic pressing method was applied to densify granulated powder. Further the sintering and annealing processes were
deployed to produce the final Nd:YAG ceramic samples. Mean grain sizes of about 20 µm and grain boundaries less than
10 nm of elaborated Nd:YAG ceramic samples were evaluated in SEM and TEM measurements. Thus, in microscale the
quality of obtained ceramic was quite satisfactory. However, in macroscale, the samples had unacceptable level of voids and
pores observed in visual inspection, which resulted in low 76% transmission, corresponding to extinction coefficient of
0.32 cm-1 at 1064-nm wavelength. The sizes of defects, pores and inclusions were of several dozens of micrometer. The
active elements of rod and slab shape were fabricated and characterized in two diode pumping laser set ups. In end pumping
configuration as a pump source 20-W fiber coupled laser diode was deployed. For the low duty cycle pumping (1 ms/20 Hz)
above 30% slope efficiency was achieved. In the best case, 3.7 W of output power for 18 W of pump power, with M2 <1.4
were demonstrated for uncoated ceramics rod of φ4x3mm size. We have used uncoated elements, thus we can expect
increase in laser parameters for optimized pumping conditions and samples with anti-reflective coatings. The parameters of
elaborated ceramic material at this stage of work are unsatisfactory for laser application. However, the results of TEM
measurements and laser characterizations seems to be quite promising..
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