Nonlinear Optical Properties of deoxyribonucleic acid DNA doped Rhodamine B/PVA films using Z-scan technique

Abstract

In this work, we present the nonlinear optical properties from the measurements of third order nonlinearity in DNA doped Rhodamine B/PVA films achieved through Z-scan technique at a wavelength of 1064nm. The films demonstrated negative nonlinear refractive index (n2) with magnitudes of (8.66-16.7) ×10-7cm2/W with varying weight concentrations of DNA. While, the largest magnitude (7.64×10-7) cm2/W with a positive (n2) was observed at different concentrations of RhB/PVA films. Open aperture data demonstrated a strong two-photon absorption with a magnitude of 26.8×10-3cm/W for films doped with (6Wt. %) of DNA. However, a nonlinear absorption coefficient (β) with a magnitude 4.77×10-3cm/W at the concentration 1×10-4 Ml of RhB/PVA film was recorded. Reverse saturable absorption (RSA) behavior at 1064 nm for RhB/PVA films was observed and by adding DNA, a strong completely switchover from RSA to SA behavior. These data indicate to the addition of DNA enhanced the nonlinear optical properties of the solid films. Therefore, suggests that DNA is promising material for photonics applications.