We show theoretically that the group velocity of light can be slowed down by means of phase coupling in the photorefractive two-wave mixing process. It is shown that the group velocity of light propagating in a photorefractive material could be significantly reduced because of a steep variation of the phase-coupling coefficient with respect to the angular frequency difference between two coupling beams in a two-wave mixing process. The results for the case of a photorefractive Bi<sub>12</sub>SiO<sub>20</sub> crystal are presented and discussed in detail.
© 2004 Optical Society of America
(050.5080) Diffraction and gratings : Phase shift
(060.5060) Fiber optics and optical communications : Phase modulation
(190.5330) Nonlinear optics : Photorefractive optics
(190.7070) Nonlinear optics : Two-wave mixing
Guoquan Zhang, Rong Dong, Fang Bo, and Jingjun Xu, "Slowdown of group velocity of light by means of phase coupling in photorefractive two-wave mixing," Appl. Opt. 43, 1167-1173 (2004)