Sub-5-fs real-time spectroscopy of coherent geometrical relaxation processes in polydiacetylenes

Author

Kobayashi, T. ; Shirakawa, A. ; Matsuzawa, H. ; Nakanishi, H.

Author_Institution

Dept. of Phys., Tokyo Univ., Japan

fYear

1992

fDate

23-28 May 1992

Firstpage

200

Lastpage

201

Abstract

Summary form only given. Ultrafast dynamics of conjugated polymers such as polydiacetylenes (PDA) has been attracting many scientists because they are model systems of quasi-one dimensional semiconductors with a strong electron-phonon coupling. From our extensive studies the initial kinetics after photo-excitation can be explained by a relaxation of a free exciton (FE) to a self-trapped exciton (STE) within 150 fs. The recent achievement of sub-5-fs visible pulse generation based on a novel noncollinear optical parametric amplification (NOPA) has enabled the real-time observation of the formation of a STE in a PDA for the first time.

Keywords

electron-phonon interactions; excitons; high-speed optical techniques; optical parametric amplifiers; optical polymers; optical pulse generation; 150 fs; 5 fs; coherent geometrical relaxation processes; conjugated polymers; free exciton relaxation; fs visible pulse generation; initial kinetics; noncollinear optical parametric amplification; photo-excitation; polydiacetylenes; quasi-one dimensional semiconductors; real-time observation; self-trapped exciton; strong electron-phonon coupling; sub fs real-time spectroscopy; ultrafast dynamics; Excitons; Iron; Kinetic theory; Nonlinear optics; Optical pulse generation; Polymers; Pulse generation; Spectroscopy; Stimulated emission; Ultrafast optics;

fLanguage

English

Publisher

ieee

Conference_Titel

Quantum Electronics and Laser Science Conference, 1999. QELS '99. Technical Digest. Summaries of Papers Presented at the

Conference_Location

Baltimore, MD, USA

Print_ISBN

1-55752-576-X

Type

conf

DOI

10.1109/QELS.1999.807533

Filename

807533