Three-photon up-conversion lasing of a novel multibranched nonlinear chromophore in doped poly(methyl methacrylate)

A novel nonlinear chromophore, 4, 4´, 4´´-tris((3,6-di-tert-butyl)-9-carbazyl-(9,9-dioctyl)-2,7-fluorenylidene-vinylidene) triphenylamine (TCFVTPA), which possesses multibranched molecular structure and extended coplanar conjugation length, has been designed, synthesized and characterized. One-photon induced photophysical properties were studied in 1×10-5 mol/L chloroform solution. Three-photon induced fluorescence was obtained in poly(methylmethacryate) (PMMA) with the doped concentration of 1×10-2 mol/L pumped by a femtosecond laser system at 1300nm and the correspoding cross-section of TCFVTPA was measured as 8.3×10-75 cm6 s2 by nonlinear transmission method. When the energy of input irr…