Theoretical Investigation of Effective Parameters on the Second Harmonic Generation Efficiency in AgGaSe2 Crystal

The Silver Gallium selenide crystal is more important than other crystals due to its intrinsic parameters. The transparency of the AGSe crystal is in the wavelength range of 10.06 microns, which uses the pulsed CO2 laser at atmospheric pressure (TEA) as the fundamental wavelength for the second harmonic generation. Therefore, the effect of parameters such as intensity, nonlinear crystal length, temperature and wavelength on the phase–mismatched and efficiency has been investigated. The coupled- wave equations are performed numerically by MATLAB software. The results indicate the existence of optimal length in the efficiency of the second harmonic generation in the crystal. In a crystal with a length of 1.05 cm, the efficiency reaches 80.35%. Also, the maximum efficiency of the second harmonic generation is 0.025W/cm2 (threshold intensity) and the crystal length is 0.5 cm. The results of modeling and numerical calculations in this work are in good agreement with the experimental results of others.