Electrospun polymer nanofibers decorated with Ag/Au nanoparticles — A smart material with enhanced nonlinearity

Functionalization of the surface and interior of nanofibers with nanoparticles by electrospinning process is an efficient fabrication technique for a wide variety of nanoparticle embedded materials. In the present study, it was aimed to compare the third order nonlinear absorption coefficient of the Ag/Au nanoparticles incorporated nanofibers with the casted films of Casein/Polyvinyl pyrrolidone (CAN/PVP) Au/Ag nanocomposites as well as CAN/PVP blend. Linear optical studies and morphological analysis of the CAN/PVP Au/Ag nanocomposite films and nanofibers confirms the efficient distribution of nanoparticles into the matrix. Open aperture Z-scan measurements at 532 nm, 5 ns laser pulses exposed that nanofibers with Au/Ag nanoparticles exhibited higher two photon absorption coefficient than its nanocomposite solution. This augmentation is correlated with the morphology of nanofibers and electric field enhancement of Au/Ag nanoparticles into the matrix. Optical limiting performance of the prepared CAN/PVP Au/Ag nanocomposites and nanofibers offer a better result than the CAN/PVP blend due to the nonlinear absorption of the nanoparticles in resonant and nonresonant regime, thus making it suitable for various optical limiting applications.