Enhanced nonlinear optical performance of electro-spun 5C2NA-PEO fibers

In this study, we synthesized electro-spun fibers of 5-Chloro-2-Nitroaniline (5C2NA) embedded in polyethylene oxide (PEO) in submicron range. We conducted comprehensive analysis of these fibers, including their morphological, structural, vibrational, mechanical, linear and nonlinear optical properties. Nonlinear optical effects such as saturable absorption (SA) and reverse saturable absorption (RSA) are our particular interest of investigation for this report, which play a crucial role in the development of all-optical logic gates and optical limiting devices. The transition between SA and RSA is especially significant for optoelectronic applications. Using the Z-scan technique, we demonstrated the ability of 5C2NA-PEO fibers to show RSA and SA together under varying pump intensities. The nonlinear optical parameters such as nonlinear absorption coefficient and limiting threshold have been calculated and compared with bulk 5C2NA. An enhancement in the nonlinear optical performance has been noticed in fibrous form. The nonlinear absorption has been found to be increased almost five times and optical limiting threshold is reduced three times. Higher nonlinear absorption and lower limiting threshold of the materials always extends its utility for applications. These switching properties of 5C2NA-PEO fibers with enhanced performance hold promise for various applications such as logic gates, optical switching and optical limiting.