90° phase-matched direct third-harmonic generation in LiIO_3

摘要

Phase-matching properties for harmonic generation via second- and third-order nonlinearities have been investigated in LiIO_3 using the Nd:YAG laser and its harmonic pumped parametric oscillator. It was found that this crystal is 90° phase-matchable for direct type-2 third-harmonic generation (THG) at 0.3568 μm at 20 °C. In addition, the temperature acceptance bandwidths have been measured for second-order processes and were used for construction of the thermooptic dispersion formula. The Sellmeier equations that correctly reproduce almost all of the experimental data in the whole transmission range are also presented.