The presence and absence effect of the template on optical nonlinearity responses of magnetic moleculary imprinted polymer

A magnetic moleculary imprinted polymer (MMIP) was prepared by polymerization reaction of 4-vinylpyridine, magnetic vinylsilane, and crosslinker agent ethylene glycol dimethacrylate in the presence of octahydroquinazolinone target molecule entitled the "template" which had the selective capability of bonding and rebinding. The effects of the presence and absence of template on third-order nonlinear optical responses (NLO) of MMIP at 532 nm were investigated by the application of the Z-scan technique. All samples had the negative reflective index with self-defocusing effect in the order of 10^{- 8} cm²/W, and the absorption coefficient in the order of 10^{- 4} cm/W. Moreover, all samples had a valley in the nonlinear absorption coefficient that shows the two-photon absorption (TPA) effect as a dominant phenomenon. The NLO properties of samples were improved by increasing the incident power of laser. Furthermore, the third-order susceptibility, χ⁽³⁾, and figure of merit (FOM) of samples were calculated. The polarity, charge transferring and porosity in MMIP are the most important factors for having more nonlinearity responses in comparison with other samples. In addition, the MMIP was investigated using SEM/EDX and TEM measurements to check the quality and homogeneity of them, which was essential in photonic device production.