Doubly 1,3-butadiyne-bridged ditwistacene with enhanced ultrafast broadband reverse saturable absorption

Abstract

Two-photon absorption-induced excited singlet state absorption is a good away to realize optical power limiting behavior of different laser pulses with high linear transmittance. Herein, we report a novel stable dual-mode absorption material that contains twistacene chromophores and a double 1,3-butadiyne-bridge. The formation of the dehydro[12]annulene bridge by incorporating double 1,3-butadiyne units into twistacene successfully enlarges the ultrafast reverse saturable absorption without sacrificing the features of broadband excited singlet state absorption of twistacene, where the maximum TPA cross section is up to 9564 GM, as measured by the open-aperture Z-scan and two photon-excited fluorescence methods. Meanwhile, the ability of response to various laser pulses is greatly improved. This strategy of a double bridge model is a key feature to obtain efficient ultrafast dual-mode optical limiters.