Optical spectroscopy of Nd3+/Mg2+ co-doped LiTaO3 laser crystal

Abstract

A Nd3+ and Mg2+ co-doped LiTaO3 single crystal has been grown successfully by the Czochralski method. The polarized absorption spectra of the crystal were measured and investigated. The peak absorption cross-sections at 806 and 810 nm were 4.17 × 10−20 cm2 and 4.47 × 10−20 cm2 with a full width at half maximum of 29 and 17 nm for σ- and π-polarization, respectively. Based on the Judd–Ofelt theory, the spectral parameters of Nd3+ in the as-grown crystal were investigated in detail. Moreover, the emission probabilities, branching ratio and radiative lifetime for the transitions from 4F3/2 were calculated. The radiative lifetime of 4F3/2 was calculated to be 159 μs and the luminescent quantum efficiency of the 4F3/2 manifold was about 81.13%. The results were also compared with other Nd3+ doped crystals.