The defects in heavily MgO-doped single crystals were investigated by means of optical absorption and Raman spectroscopy, together with Ar+ irradiation of heavily MgO-doped samples. A new threshold effect, the formation of MgNb, was observed for 10mol%MgO.

Configuration of MgNb Defects in Heavily Mg-Doped LiNbO3 Single Crystals. I.W.Kim, B.G.Moon, J.J.Jeong, H.L.Park, V.F.Pichugin: Materials Letters, 2001, 49[6], 324-6