Effect of [Li]/[Nb] ratio on composition and defect structure of Zr:Yb:Tm:LiNbO3 crystals

Abstract

Zr:Yb:Tm:LiNbO3 crystals with various [Li]/[Nb] ratios (0.946, 1.05, 1.20 and 1.38) were grown by the Czochralski technique. Distribution coefficients of Zr[Formula: see text], Yb[Formula: see text] and Tm[Formula: see text] ions were analyzed by the inductively coupled plasma-atomic emission spectrometer (ICP-AES). The influence of [Li]/[Nb] ratio on the composition and defect structure of Zr:Yb:Tm:LiNbO3 crystals was investigated by X-ray diffraction and IR transmission spectrum. The results show that as the [Li]/[Nb] ratio increases in the melt, the distribution coefficients of Yb[Formula: see text] and Tm[Formula: see text] ions both increase while that of Zr[Formula: see text] ion deceases. When the [Li]/[Nb] ratio increases to 1.20 in the melt, Zr:Yb:Tm:LiNbO3 crystal is nearly stoichiometric. In addition, when the [Li]/[Nb] ratio reaches up to 1.38, Nb[Formula: see text] are completely replaced and Li[Formula: see text] starts to impel the Zr[Formula: see text], Yb[Formula: see text] and Tm[Formula: see text] into the normal Li sites.