Influence of composition of MgO-doped lithium niobate on phase-matching temperature for frequency doubling in the visible

Abstract

The dependence of the phase-matching temperature for second harmonic generation (SHG) of 1064-nm radiation on Li/Nb and Li/Mg ratios in MgO-doped lithium niobate crystals was investigated. Crystals studied were grown from melts with 0, 1, 2, and 5 mol % MgO and were equilibrated to different Li contents through a vapor-phase-transport process. Crystals with no MgO doping, equilibrated to the Li-rich phase boundary, had the highest phase-matching temperature. At room temperature (25.5°C), this material phase-matched for SHG of 978.4-nm radiation to generate blue light.