Studies on low power optical phase conjugation (OPC) in three
saturable dyes, viz., eosin, erythrosin B, and rose bengal, embedded in two
polymer films, viz., gelatin and polyvinyl alcohol, are presented. Experiments
are performed using the 514.5 nm line of an argon-ion laser. Saturation
intensities are determined from the transmission versus intensity plots, and
triplet lifetimes are estimated from the phosphorescence decay curves. OPC
experiments are performed, and the variation of OPC reflectivity with intensity
and absorption length is studied. Experimental results are compared with the
theory of degenerate four-wave mixing in absorbing media proposed by R. L.
Abrams and R. C. Lind [Opt. Lett. 2(4), 94 (1 978)]. There is fair agreement
between the theory and the experimental observations. The limitations in using
these films for cw OPC applications are briefly discussed.