Nonlinear Optical Properties of SWCNTs Incorporated Silica Composites

HiPco and Arc-made single-walled carbon nanotubes (SWCNTs) were incorporated into silica matrices via a conventional sol-gel method to form SWCNTs/silica composites. Optical absorption and FT-Raman spectroscopy revealed that purification process using acid treatment resulted in preferential removal of metallic SWCNTs and severe damage and/or side-wall functionalization of HiPco SWCNTs. Z-scan measurements of SWCNTs/silica composites showed self-defocusing and bleached absorption phenomena which indicated that both the real and imaginary parts of X³, the third-order nonlinear optical susceptibility, of these composites had negative sign.