Frequency conversion of near IR lasers in AgxGaxGe1-xS2 and AgxGaxGe1-xSe2

The linear and nonlinear optical properties of AgxGaxGe1-xS2 (AGGS) at x = 0.20, 0.25, and 0.50 and AgxGaxGe1-xSe2 (AGGSE) at x = 0.17 and 0.25 have been investigated for second-harmonic generation (SHG) of near IR lasers. The polarization dependent transmission curves of these crystals showed larger energy band-gaps for polarization parallel to c axis than that for a axis. The 90° phase-matched SHG wavelengths measured along b axis at room temperature were found to be 0.515, 0.530, and 0.774 μm for the AGGS samples at x = 0.20, 0.25, and 0.50, and 0.638 and 0.676 μm for the AGGSE samples at x = 0.17 and 0.25, respectively. In addition, the crystal to crystal and local variations of the phase-matching conditions are presented together with their temperature stability.