Effect of post treatment on the photorefractive properties of Ru-doped lithium niobate

✍ Scribed by Chang-Hung Chiang; Jyh-Chen Chen; Jenq-Yang Chang; Chung-Wei Lu

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 269 KB
• Volume: 42
• Category: Article
• ISSN: 0232-1300
• DOI: 10.1002/crat.200711022

✦ Synopsis

Abstract

The effect of post treatment on the photorefractive properties of Ru‐doped lithium niobate was studied. The absorption spectra examination of Ru‐doped LiNbO~3~ crystals with different post treatments showed that the absorption coefficient at 530 nm increased after the reduced treatment was employed and the absorption edge of the reduced crystal shifted towards the infrared band. On the contrary, the trend reversed after the oxidized treatment was employed. In addition, the photorefractive properties were investigated with the two‐beam coupling method conducted via a 532 nm solid state laser. It was found that the oxidized Ru:LiNbO~3~ had smaller exponential gain coefficient and diffraction efficiency because the charges in the shallow level were exchanged to the deep level. On the other hand, the reduced Ru:LiNbO~3~ crystals had larger exponential gain coefficient and diffraction efficiency due to the increase of the Ru^3+^ which existed in the shallow level. The response times of both oxidized and reduced Ru:LiNbO~3~ were longer than those of the as‐grown ones. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)