ИСТИНА

YVO4 and LuVO4 attract attention due to their chemical and radiation stability as well as remarkable luminescence properties. A development of the mixed crystals based on YVO4 and LuVO4 may allow to obtain a material with better properties than those of its constituents. Presence of Lu provides high stopping power that is important for the material’s application as scintillators or X-ray phosphors. Mixed crystals in some cases demonstrate enhanced luminescence properties due to a non-linear effect of the increase of the efficiency of excitation energy conversion into luminescence]. Moreover, the mixed crystals may allow to supress the influence of point defects on the relaxation processes. Point defects, which usually occur in complex oxides and worsen the material’s performance can be buried by the states of the conduction and/or valence bands by tuning the ratio between cations, even in the case when defect’s concentration is not reduced. The goal of this work is a study of defect structure as well as luminescence and electronic, properties of the vanadate mixed crystals LuxY1-xVO4. Presence of point defects and related charge traps was studied by thermally stimulated luminescence (TSL) method. All observed TSL curve have complicate structure. In case of undoped mixed crystals the TSL peaks were observed in the temperature range 80-230 K. For mixed crystals doped Eu3+ the TSL curves were detected in range 80 - 300 K. The structure of TSL curves becomes more complicated in the mixed crystals. Additional nonelementary peak was observed for mixed compounds of doped vanadates in temperature range 230-270 K. The origin of the traps will be discussed in the report. The shift of TSL peaks does not occur with change of x value that indicates the nonexistence of a modification of bandgap edges.