Photovoltaic effect and photorefraction in LiNbO3: Mg crystals

With relation to photorefraction, it has been found that higher light irradiation intensities can be withstood by Li-rich LiNbO3:Mg (5 mol%) than by the congruent LiNbO3:Mg (5 mol%). The photoconductivity of the former is an order of magnitude larger than that of the latter. Doping with 0.1 wt% Fe in Li-rich LiNbO3:Mg (5 mol%) does not distinctively alter its ability to resist photorefraction. The photovoltaic currents of Li-rich LN:Mg:Fe and Li-rich LN:Mg are nearly equal and are two orders of magnitude smaller than that of LN:Fe. The photoconductivity of Li-rich LN:Mg:Fe is an order of magnitude smaller than that of Li-rich LN:Mg and is much larger than that of LN:Fe.