Two-photon absorption cross-section investigation of visible-light photoinitiators under Q-switched Nd:YAG nanosecond pulse laser at 1064 nm

Two-photon polymerization (TPP) technologies commonly rely on femtosecond lasers such as Ti:sapphire which limits their accessibility due to high costs and complexities. Recently, multiple reports showed TPP under near-infrared irradiation enables the use of alternative light sources Neodymium-doped known be affordable efficient for a nanosecond picosecond pulsed generation. 4,4′-Bis(dimethyl-amino) benzophenone or Michler’s ketone (MK), one photoinitiators used photopolymerization UV irradiation, also shows an absorption band in visible region allows two-photon at fundamental wavelength 1064 nm. In this report, we investigated (TPA) MK contrast with Irgacure-784 Indane-1,3-dione, reported promising same process. Among them, large TPA cross-section measured via nonlinear transmission method Z-scan technique Q-switched Nd:YAG pulse laser nm, demonstrating photoinitiator low-cost polymerization.