Crystal growth and thermal annealing of AgGaGe5Se12 crystal

Abstract

AgGaGe5Se12 is a new quaternary nonlinear optical crystal which is applied to laser frequency conversion, especially converting 1.064 µm light to mid-IR range. In this work, we have synthesized the AgGaGe5Se12 polycrystal by the two-zones temperature method. By the modified Bridgman method, we have grown high-quality AgGaGe5Se12 single crystal 30 mm in diameter and 50 mm in length. The structure refinement was carried out by the Rietveld method. Besides, the XRS results were analyzed by comparing with AgGaGeS4 and AgGaGe5S12. In addition, the non-polarized Raman spectra were recorded and the intense peaks were observed at 200 and 232 cm−1. The peaks were attributed to corner-sharing (CS) and edge-sharing (ES) clusters. At last, the crystal was characterized by a high transparency in the 0.6–15 µm spectral range and the absorptions at 3.4 and 7 µm, observed in the as-grown crystal, have been eliminated after annealing. Thus, AgGaGe5Se12 is appropriate for further optical experiments and more comprehensive applications.