Ceramic Nd:YAG microchip provides high-efficiency laser output
Working with the Japanese Technical Research Center (Kitakyushu, Japan) and Osaka Institute of Technology, researchers at the Japanese Institute for Molecular Science (Okazaki) recently demonstrated high-efficiency lasing from a diode-pumped ceramic chip of Nd:YAG. The polycrystalline YAG ceramic allows high neodymium doping levels that overcome the low absorption cross section; the absorption coefficient of a conventional Nd:YAG crystal is 3.45 cm-1 at 808 nm for a neodymium concentration of 0.9 at.%--at the 4.8 at.% used in their experiment, the researchers report absorption of the Nd:YAG ceramic as about 10 cm-1. The result is a device that produces an output power four times that of a conventional Nd:YAG crystal. According to researcher Takunori Taira, scattering losses for the ceramic microchip are much lower than for conventional ceramics. The test results, which were presented at February`s OSA Advanced Solid State Laser conference (Boston, MA), indicate that the Nd:YAG ceramic has potential as a microchip laser. Contact Takunori Taira at [email protected].