Saturable absorption in graphene oxide-doped acrylate polymer used for direct laser writing

Graphene oxide (GO) has gained attention in the graphene family owing to its optical and electrical properties. Besides, it is low-cost and water-soluble compared to graphene, thus holding a great potential for large-scale and cost-effective production of graphene-based materials. Several works report the 2D patterning of GO-based materials, though the fabrication of 3D micro/nanodevices based on GO is still on demand. In this work, we investigated the saturable absorption behavior of graphene oxide incorporated in an acrylate polymer, aiming at the development of microdevices to be fabricated via direct laser writing. The nonlinear measurements of such composite were carried out through the femtosecond Z-scan technique with excitation at 1550 nm. By modeling the photo-carrier dynamics with a two-level system, we found the saturation intensity to be 500 MW/cm
²
, which is consistent with what is expected for graphene derivatives excited in the transient regime.