Abstract

The attempt to synthesize the solid-state laser material of polycrystalline Nd:YAG ceramics were reported by With et al and by Sekita et al. However, the laser oscillation of these ceramics wasn't observed. We have succeeded to fabricated a transparent Nd:YAG ceramics with nearly equal to those of a single crystal. A simple, solid-state reaction among Al₂O₃, Y₂O₃ and Nd₂O₃ powders (>99.99 wt. %) was used in this fabrication method. The powder of Al₂O₃, Y₂O₃ and Nd₂O₃ was synthesized by alkoxide precipitation, pyroiysis of Y₂(OH)Cl₅ · nH₂O and oxalate precipitation, respectively. These starting powers were weighed so that the Nd content in the resultant YAG ceramics would be 1.1 at %. The milled slurry (mixed powder in alcohol) was dried using a spray dryer. The dried powders were isostatically pressed at 140 MPa into disks 16 mm in diameter. Specimens for optical measurement were sintered at 1750°C for 1 ~ 50 hr in vacuum (1.3 × 10³ Pa). The specimen was excited continuously with an 808-nm diode laser and the laser beam of Nd:YAG (1.06 µm) emitted from half mirror was measured using an optical power meter.

© 1995 IEEE