Growth and spectroscopic properties of LiNbO3 single crystals doped with Nd3+ and Yb3+ ions

The LiNbO3 crystals doubly doped with Nd3+ and Yb3+ ions were pulled by the Czochralski method. The optical homogeneity of the crystals was investigat ed using the residual birefringence maps. The optical properties of the cry stals were investigated. The Nd-Yb energy transfer takes place in this syst em. The positions of the F-4(3/2) level of Nd3+ and of the ground F-2(7/2) and excited F-2(5/2) levels of Yb3+ are determined. The splittings observed in the low temperature emission spectra prove that both Nd3+ and Yb3+ occu py more than one site in the crystal host. (C) 1999 Elsevier Science B.V. A ll rights reserved.