Efficient mid-infrared laser using 1.9-mu m-pumped Ho : YAG and ZnGeP2 optical parametric oscillators

摘要

We report >4.2-W mid-infrared (mid-IR) output (3.8 and 4.65 mu m) and >2.1 W at 3.5 mu m in ZnGeP2 (ZGP) optical parametric oscillators (OPO) pumped by a holmium-doped yttrium aluminum garnet (Ho:YAG) laser, directly pumped by a diode-pumped 1.9-mu m thulium-doped yttrium lithium fluoride (Tm:YLF) laser. Optical-to-optical efficiency achieved is >7.2% (laser diode to mid-IR). In addition, a Ho:YAG-pumped ZGP OPO operation is achieved over a Ho:YAG temperature range of 80 degrees C at the 8-W (Ho:YAG) and 3-W (ZGP OPO) power levels. (C) 2000 Optical Society of America [S0740-3224(00)00905-X]. OCIS codes: 140.0140, 140.3070, 140.3480, 140.3580, 140.5680, 190.4970. [References: 14]