The influence of beam coupling on photorefractive parametric oscillation generated in a Bi<sub>12</sub>SiO<sub>20</sub> crystal is investigated experimentally by comparing two configurations with and without the presence of beam coupling. It is shown that beam coupling has a great influence; for example, the transversal split of the <b>K</b>/2 subharmonic grating is seen only in the beam-coupling geometry. A case that resembles <b>K</b>/4 subharmonic generation can, however, still be found in the absence of beam coupling.
© 1998 Optical Society of America
Henrik C. Pedersen, D. J. Webb, and Per M. Johansen, "Influence of beam-coupling on photorefractive parametric oscillation in a dc-field-biased Bi12SiO20 crystal," J. Opt. Soc. Am. B 15, 2439-2445 (1998)