comparison of Lu3Al5O12:Ce(Er) bulk and nano single crystals

Lutetium aluminum garnet (LuAG) is a crystal well known for being extraordinarily useful for building highly efficient laser devices or ionizing radiation detectors.To design the most favourable physical properties, different dopants and synthesis methods are constantly developed, primarily focused on the advantages of single crystals.However, the downscaling of the luminescent materials to nanosize also creates additional benefits of increased surface to volume ratio and thus, the efficiency of luminescence or doping can be improved.Therefore, the aim of this work is to compare the single crystals and nanogarnets under the influence of Ce and Er doping.Optical properties of the garnet single crystals are very well known while the nanocrystals should have been studied first.Synergy methods like X-ray diffraction (XRD), photoluminescence (PL), photothermal deflection spectroscopies (PDS) were applied to the LuAG:Ce(Er) nanocrystals whereas the electron paramagnetic resonance (EPR) measurements were carried out in both single and nanocrystals.The main conclusion is that cerium enters nanocrystalline lattice becoming Ce 4+ compensated by the Cr 2+ , Fe 2+ ions (accidental impurities) whereas it is also Ce 3+ in the single crystal.About one order of magnitude larger Er 3+ content was observed in the case of nanocrystals as compared to single crystals.