Two-photon absorption of new multibranched chromophore with dibenzothiophene core

A series of novel chromophores with dibenzothiophene core and triphenylamine-branch have been synthesized to investigate two-photon absorption (TPA) by Ti:sapphire femtosecond laser pulse at 800 nm. The comparative studies on the linear and nonlinear optical properties for the ‘bridge’ and ‘branch’ segments within chromophores were conducted, which showed the linear absorption of chromophore originating from the individual ‘branch’; the emission, however, not from the ‘bridge’ duo to the V-style geometry for dibenzothiophene-based chromophores. Strong interaction couplings between individual ‘branch’ via dibenzothiophene core have been observed, which results in larger TPA cross-section and stronger two-photon induced fluorescence with the generation number increasing.