We measure and analyze beam-coupling gain and response time in BaTiO3 crystals doped with cobalt at levels of 50 and 100 parts in 106 for various oxidation and reduction states. We discuss the effect of cobalt doping and oxidation–reduction on the electron paramagnetic resonance and optical absorption of BaTiO3. We compare the BaTiO3:Co samples with nominally undoped and transition-metal- (chromium, manganese, iron, and iron + nickel) doped BaTiO3. We conclude that cobalt-doped BaTiO3 in the as-grown state displays high photorefractive gain that is correlated with the cobalt concentration in a reproducible manner. Cobalt appears to be the most promising transition-metal dopant for BaTiO3 investigated so far.
© 1990 Optical Society of America
Original Manuscript: May 16, 1990
Manuscript Accepted: July 30, 1990
Published: December 1, 1990
Daniel Rytz, Barry A. Wechsler, Mark H. Garrett, Charles C. Nelson, and Robert N. Schwartz, "Photorefractive properties of BaTiO3:Co," J. Opt. Soc. Am. B 7, 2245-2254 (1990)