Femtosecond transient bleaching decay in poly(alkyl-thiophene-vinylene)s in solution and in film

Abstract We report on ultrafast absorption measurements on poly(3,4-dibutyl-thiophene-2,5-diyl-vinylene) using the pump and probe technique. Transient photoinduced bleaching has been measured both in chloroform solution and in film. A complete and fast absorption recovery after photoexcitation occurs in solution, while a long-lived component is observed in film. The comparison of the temporal behavior of the initial transient bleaching decay between solution and film allows us to evaluate the contribution of the vinyl group to the backbone rigidity. The observed excited state dynamics is interpreted in terms of polaron-exciton recombination on deformation centers whose concentration and distribution depend on the supermolecular organization of the sample.

[1]  Y. Gartstein.  Intrachain photoconductivity of conjugated polymers from polaron pairs , 1990 .

[2]  R. Yen,et al.  Picosecond Dynamics of Photoexcited Gap States in Polyacetylene , 1982 .

[3]  N. Oyama,et al.  Electropolymerization of fused pyrroles as new heteroaromatic polymers , 1989 .

[4]  Alfano,et al.  Interchain interactions in polyacetylene: Optical properties and photoconductive response. , 1992, Physical review. B, Condensed matter.

[5]  Richard C. Powell,et al.  Singlet exciton energy transfer in organic solids , 1975 .

[6]  L. Williams,et al.  Picosecond relaxation dynamics in polydiacetylene-pTS , 1987 .

[7]  S. Silvestri,et al.  New configuration for highly stable hybrid mode-locked femtosecond dye lasers , 1992 .

[8]  Paul D. Townsend,et al.  Photo-excitation in conjugated polymers , 1987 .

[9]  David C. Torney,et al.  Diffusion-limited reactions in one dimension , 1983 .

[10]  A. J. Heeger,et al.  Infrared activity of photoexcitations in polythiophene , 1986 .

[11]  Takayoshi Kobayashi,et al.  Ultrafast optical response in polydiacetylenes and polythiophenes , 1991 .

[12]  W. Porzio,et al.  The structure of neutral polythiophene. An application of the rietveld method , 1988 .

[13]  R. L. Elsenbaumer,et al.  Handbook of conducting polymers , 1986 .

[14]  Uwe Stamm,et al.  Relaxation dynamics of photoexcitations in polydiacetylenes and polythiophene , 1990 .

[15]  W. R. Salaneck,et al.  Theoretical study of the influence of thermochromic effects on the electronic structure of poly(3-hexylthiophene) , 1989 .

[16]  S. Silvestri,et al.  On the stability, mode properties, and misalignment sensitivity of femtosecond dye laser resonators , 1991 .

[17]  Y. Gaididei,et al.  Random walks of a pair of annihilating quasiparticles on defected chains , 1988 .

[18]  A J Heeger,et al.  Polyacetylene, (CH)x: The Prototype Conducting Polymer , 1982 .

[19]  High-pressure effects on ultrafast-relaxation kinetics of excitons in polydiacetylene 4BCMU. , 1991, Physical review letters.

[20]  J. RiceMichael.  Comment on «photoexcitations in trans-(CH)x; A Fourier transform infrared study , 1983 .

[21]  R. Friend,et al.  Transient absorption and reflectivity studies of poly(2,5-thienylene vinylene) , 1991 .

[22]  Donal D. C. Bradley,et al.  Photoexcited states in poly(3-alkyl thienylenes) , 1990 .

[23]  S. Etemad,et al.  Photoinduced absorption in a polydiacetylene , 1984 .

[24]  Choi,et al.  Excited polarons in poly(phenylene vinylene) and poly(diacetylene). , 1991, Physical review. B, Condensed matter.

[25]  Graham,et al.  Femtosecond optical absorption in poly(3-alkyl thienylene)s. , 1991, Physical Review B (Condensed Matter).