[Spectroscopic analysis of Er3+ in Er3+ /Yb3+ co-doped LiNbO3 crystal].

At room temperature, alpha-polarized absorption spectra of as-grown and annealed Er3+/Yb3+ co-doped, Z-cut LiNbO3 single crystals, grown by using Czochralski method, were measured in the wavelength range of 300-1 650 nm. The spectroscopic properties of Er3+ were analysed by using Judd-Ofelt theory. The experimental values of the electron transition strengths of several major transitions from the ground state to excited-state manifolds were evaluated from the measured integrated absorption coefficients of Er3+.