Abstracts

The current development of laser materials technology can be determined, in a broad sense, by the goal of increasing their power and efficiency. For common applications, the economic aspect is also important. Both of these criteria are addressed by new high optical quality ceramic laser materials doped with rare earth ions. The properties of transparent yttrium aluminum garnet ceramics doped with Nd³⁺ and Sm³⁺, which theoretically meet all the criteria for laser and cladding materials, respectively, were investigated. The phase formation, microstructure evolution, thermal properties, refractive index and spectroscopic properties of Y₃Al₅O₁₂ (YAG) ceramics with different concentrations of Nd³⁺ (0.5-4 at.%) and Sm³⁺ (1-10 at.%) were determined. In result, absorption, excitation, Raman spectra and thermoluminescence curves were measured and correlated with microstructural properties. Low-temperature experiments were also carried out to validate the possibility of using both materials also under cryogenic laser operating conditions. In the case of heavily doped YAG, not only the refractive index of these materials and the conductivity, but especially the concentration of defects can change, leading to non-radiative processes. Based on the results, it was possible to determine the appropriate dopant concentrations for optimal performance of a future ceramic laser operating in the low-temperature regime.