Nonlinear Optical Response of Hydroxy Substituted Anthraquinone/PMMA Thin Films Using Z-Scan Technique

The present work reports the nonlinear optical studies of hydroxy substituted anthraquinone organic dyes. The 1,2-dihydroxy-Anthraquinone, 1,4-dihydroxy-Anthraquinone and 1,5-dihydroxy-Anthraquinone are embedded in a polymethyl methacrylate to synthesize composite thin films by adopting guest-host method. The nonlinear refraction, nonlinear absorption and third order susceptibility have been evaluated by employing Z-scan technique using low power continuous laser operating at 532 nm. The samples exhibits positive nonlinear absorption (or reverse saturable absorption) and negative nonlinear refraction. The estimated values of coefficient of nonlinear absorption, nonlinear refraction and third order susceptibility are of the order of 10⁻³ (m/W), 10⁻¹⁰ (m²/W) and 10⁻⁴ (esu), respectively. These nonlinear optical effects obtain, sensitive even to low intensity excitation, suggest the new organic dye-polymer composite materials for an application in nonlinear optical devices.