Spectroscopic properties of near-stoichiometric In:Er:LiNbO3 crystals

► In(2 mol%):Er(1 mol%):LiNbO3 crystals with [Li]/[Nb] of 0.946 and 1.38 are grown. ► The absorption spectra are analyzed by Judd-Ofelt (J-O) theory. ► The lattice environment of Er3+ changes greatly and the threshold concentrations decrease with the increase in [Li]/[Nb] ratios. ► The second harmonic generation light can be easily generated in In:Er:SLN without any strict phase matching.