The influence of Zn2+ ion on the 1.5 μm laser properties of LiNbO3 crystal heavily doped with Er3+ ion

The spectral characteristics of 1.54 mu m emission in a series of Zn/Er:LiNbO3 crystals with heavy Er content and variable Zn content were reported. The inductively coupled plasma mass spectrometry (ICP-MS) was used to determine the concentration of Er3+ ion in the crystal. The absorption and emission spectra of Zn/Er:LiNbO3 crystals were measured. Based on Judd-Ofelt theory, the spectral parameters such as intensity parameters ohm(t) (t=2, 4 and 6), transition strengths, radiative transition probabilities, radiative lifetime and fluorescence branching ratio have been obtained in Zn/Er:LiNbO3 system. The emission cross section corresponding to I-4(13/2)-> I-4(15/2) transition of Er3+ ion was obtained according to Fuchtbauer-Ladenburg theory. The gain cross section of Er:LiNbO3 crystal codoped with 6 mol% Zn2+ ions were also discussed in this work. (c) 2012 Elsevier Ltd. All rights reserved.