PHOTOREFRACTIVE EFFECT IN HYDROGEN-REDUCED BATIO3

Optical and photorefractive properties of hydrogen-reduced BaTiO3 are investigated. Hydrogen-reduction induced a broad optical absorption ar ound 620 nm. From two beam coupling, the electrooptic gain is highly d ependent on intensity, with electrons being the major carriers. When t he annealing temperature increases, the electrooptic gain decreases, t hough the trap density increases. From light-induced erasure decay mea surement, the response time has a little change with intensity at low intensity, though it is much faster than that of the as-grown sample. These properties can be attributed to high dark conductivity of the re duced sample. The dark conductivity increases about three orders after hydrogen-reduction. It is about 6.6 x 10(-11) 1/(cm Omega) for the re duced sample, compared with 2.3 x 10(-14) 1/(cm Omega) for the as-grow n.