Study on a new IR nonlinear optics crystal CsGeCl_3

摘要

Oxides and chalcopyrites semiconductor materials have infrared laser properties noticed in the infrared region, but their application was restricted due to their disadvantages. So CsGeCl_3 has been studied because of its very wide-band transparency range and higher nonlinear optical coefficients. This letter will report on the crystal growth and properties of CsGeCl_3. Transparent crystals have been grown from a HCl-EtOH-CsCl mixture solution and its transparency region was found to be up to 20 μm. It has no congruent melting point and it decomposes at 325℃. Powder double-frequency studies show that its SHG signal was about 5 times to that of KDP and damage threshold was up to 200 M W/cm~2. These results show that CsGeCl_3 is a potential material for frequency-doubling application in the infrared region.