Refractive Index Measurement and Second Harmonic Generation in a Series of LiNbO₃:Mg (5mol%) Crystals

The accurate refractive indices in visible range and their Sellmeier equations have been obtained for a series of LiNbO₃ :Mg (5mol%) crystals with Ti or Nd doping. The phase matching angle for 1.064μm calculated by Sellmeier equation gives good agreement with experimental value. The TiO₂ and Nd₂O₃
doping cause the decrease of the birefringence and the increase of the phase matching angle. The conversion efficiency is enhanced by TiO₂ doping. The second harmonic generator with conversion efficiency of more than 44% has been achieved at room temperature with phase matching angle close to 90 °.