Yb:KGW and Yb:KYW Crystals Lithuania - Research - Laser And Photonic - Laser Crystals, 13 years ago, 907 hits Yb3+ doped KY(WO4)2 (KYW) and KGd(WO4)2 (KGW)single crystals are the new laser crystals for diode and laser pumped solid-state laser applications.