Poornesh, P.Hegde, P.K.Umesh, G.Manjunatha, M.G.Manjunatha, K.B.Vasudeva Adhikari, A.V.2026-02-052010Optics and Laser Technology, 2010, 42, 1, pp. 230-236303992https://doi.org/10.1016/j.optlastec.2009.06.018https://idr.nitk.ac.in/handle/123456789/27508An experimental investigation of the third-order nonlinear optical properties of new poly{2-{5-[3,4-ditetradecyloxy-5-(1,3,4-oxadiazol-2-yl)thiophen-2-yl]-1,3,4-oxadiazol-2-yl}pyridine} (P) in tetrahydrofuran (THF) solution and in solid poly(methylmethacrylate) (PMMA) matrix, by Z-scan technique is reported. The Z-scan traces reveal that the composite films exhibit large negative nonlinear refractive index of the order 10-10 esu. The excited-state absorption cross-section was found to be larger than the ground-state absorption indicating that the operating nonlinear process is reverse saturable absorption (RSA). The new polymer P exhibits good optical power limiting properties in the nanosecond regime in solution and as well in solid PMMA matrix. © 2009 Elsevier Ltd. All rights reserved.Based conjugated polymersExcited state absorptionExperimental investigationsGround state absorptionmatrixNon-linear opticalNonlinear processNonlinear refractive indexOptical power limitingPMMA matricesPoly(methyl methacrylate)Reverse saturable absorptionReverse saturable absorption (RSA)TetrahydrofuransThird order nonlinear optical propertiesZ-scanZ-scan techniqueZ-scan tracesAbsorptionComposite filmsLight transmissionOptical materialsOrganic polymersRefractive indexSolid solutionsThiopheneNonlinear optics