Effect of deoxyribonucleic acid on nonlinear optical properties of Rhodamine 6G-polyvinyl alcohol solution

We have investigated the effect of DNA on nonlinear optical properties of Rhodmine6G-PVA solution through open aperture Z-scan. We observed saturable absorption (SA) at 532 nm for dye solution without DNA. A strong influence on SA behavior of dye solution was observed by adding DNA. As the concentration of DNA (2 wt%) increased, we observed RSA within SA. The sample shows SA behavior away from focus and RSA behavior near the focus. Theoretical analysis has been performed using a model based on nonlinear absorption coefficient and saturation intensity. The result of present study gives an additional mechanism for the gain enhancement in dye doped DNA matrix. (C) 2011 American Institute of Physics. [doi:10.1063/1.3520657]