title: Degenerate two-photon absorption and effective optical-power-limiting properties of multipolar chromophores derived from 2,3,8-trisubstituted indenoquinoxaline.
abstract: Two analogous multipolar chromophores (1 and 2) that contained 2,3,8-trisubstituted indenoquinoxaline moieties have been synthesized and characterized for their two-photon absorption properties, both in the femtosecond and nanosecond time regimes. We demonstrated that their multi-branched framework structures, which incorporated appropriately functionalized indenoquinoxaline units, afforded large molecular nonlinear absorptivities within the studied spectroscopic range. Effective optical-power-limiting and stabilization behaviors in the nanosecond regime of dye molecule (2) were also investigated and the results indicated that such a structural motif could be a useful approach to the molecular design of highly active two-photon systems for quick-response and related broadband optical-suppressing applications, in particular for confronting laser pulses of a long duration.
authors.affiliation: Photonic Materials Research Laboratory, Department of Chemistry, National Central University, 300 Jhong-da Rd. 32001 Jhong-Li, Taiwan. tclin@ncu.edu.tw
authors.forename: Tzu-Chau
authors.initials: TC
authors.lastname: Lin
authors.forename: Fang-Ling
authors.initials: FL
authors.lastname: Guo
authors.forename: May-Hui
authors.initials: MH
authors.lastname: Li
authors.forename: Che-Yu
authors.initials: CY
authors.lastname: Liu
keywords: Heck reaction; absorption; chromophores; indenoquinoxalines; nonlinear optics