The photorefractive effect in a nominally undoped 0.91Pb(Zn<sub>1/3</sub>Nb<sub>2/3</sub>)O<sub>3</sub>–0.09PbTiO<sub>3</sub> single crystal is measured. We report what is, to our knowledge, the first observation of the photorefractive effect in Pb-based relaxor ferroelectric crystals. The crystal is grown by the flux solution method. Then it is cut into a 2mm× 4mm ×8mm piece and electrically poled along the  direction. The coupling constant of the two-wave mixing is 17cm<sup>-1</sup>, and the normalized time constant under 1-W/cm<sup>2</sup> illumination is 12 s at a wavelength of 476 nm. The effective trap density is calculated as 5×10<sup>16</sup>cm<sup>-3</sup> from the Debye screening length under the assumption of Kukhtarev’s band-transport model. The dominant carrier is identified to be holes from the direction of two-wave mixing energy transfer.
© 2003 Optical Society of America
Saori Abe, Tomoyasu Fujishima, Takashi Tsubone, Ryushi Fujimura, Hidenobu Ono, Osamu Matoba, Katsuroh Oda, Tsutomu Shimura, and Kazuo Kuroda, "Photorefractive effect in the relaxor ferroelectric material 0.91Pb(Zn 1/3Nb2/3)O3–0.09PbTiO3," Opt. Lett. 28, 420-422 (2003)