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The aim of this work has been to obtain transparent Tm, Ho:YAG ceramics (thulium doping range: 2–6 at.%, holmium doping range: 0.1–1.0 at.%) by reaction sintering using commercial powders. It has been proved that the particle size, purity and degree of agglomeration of the powders used are crucial from the point of view of the optical quality of ceramics. The spectroscopic measurements of Tm, Ho:YAG ceramics with different concentration of active ions (including transmission and emission spectra measurements) have been presented and discussed. As has been found, both concentration of holmium and thulium separately as well as the balance between them are of great importance. Energy transfer between Tm and Ho ions has been demonstrated.

In this work we discuss the UV-blue luminescent properties of LaAlO3 nanocrystals doped with thulium and doubly doped with thulium and ytterbium ions as well as PMMA-based composites doped with these nanocrystals. The set of nanopowders differing in activator concentration was manufactured and exposed to versatile optical characterization, covering measurements of emission and excitation spectra as well as luminescence kinetics profiles, which enabled discussion of main processes responsible for populating the excited states of thulium. Also, the up-conversion properties of Tm3++Yb3+:LaAlO3 nanocrystals were studied using an unique spectroscopic tool – hydrostatic pressure tuned semiconductor laser. All these experimental works enabled determination of the samples of optimal properties for further processing into a form of polymer composites, which have been characterized with respect of luminescent properties under direct and up-conversion excitation.

In this work we report the results of our investigations on luminescence properties in the visible spectral range of composite materials based on polymer matrices doped with nano-sized crystals activated by Pr3+ ions. In particular, we investigated the visible emission of YF3, LaAlO3, Al2O3 and Y2O3 nanopowders activated with Pr3+ ions, as well as PMMA-based composites doped with particles of the best luminescent properties. The basic structural characterization of the developed samples was performed, followed by versatile optical characterization, focused on measurements and analysis of excitation and luminescence spectra and fluorescence dynamics profiles. The comparison of spectroscopic features of developed materials enabled discussion of the influence of crystalline and polymer environment on luminescent properties of resulting materials as well as consideration of potential applicability of developed materials in white light emitters.

In this work, we discuss structural and luminescent properties of Al 2 O 3 nanopowders doped with Yb 3+ ions prepared by a novel method, in which organic compounds were used as a solvent and lanthanide organic derivatives, served as a rare-earth ion source. The set of samples differing in activator concentrations and particle sizes was carefully studied by means of structural and optical characterization methods. In particular, the high resolution electron and transmission microscopy has been deployed together with X-ray diffraction technique to determine fundamental structural properties of nanopowders. The optical characterization was focused mainly on basic excitation and emission features and their sensitiveness on dopant concentration and the average nanoparticle size.