BMOLogo
Publications

LMU München
Fakultät für Physik


Home

General
Research
Funding
Members
Publications
  All Publications
  PhD Theses
  Master Theses
  Search
  i Search
Lectures/Seminars
Conferences
Vacancies
Search

Internal




Impressum
(c) 2002 BMO

"Ultrafast singlet and triplet dynamics in microcrystalline pentacene films"
H. Marciniak, I. Pugliesi, B. Nickel, S. Lochbrunner
Phys. Rev. B 79, 235318 (2009)


Abstract:
The exciton dynamics of microcrystalline pentacene films is investigated by femtosecond pump probe experiments. Measurements are performed with ultrashort laser pulses applied at normal incidence and at an angle of incidence of 65° to disentangle singlet and triplet contributions by exploiting the different orientations of the molecular transition dipoles. The results indicate that the initial 70 fs fast relaxation step transforms the optically excited excitons in a reasonable mobile species with strongly reduced radiative transition strength. Fission into triplet excitons takes place on the picosecond timescale as a secondary, thermally activated process and with a small total yield of approximately 2%. Evidence is provided that the dominant species are singlet excitons with excimer character. To the subsequent dynamics contribute diffusion driven exciton-exciton-annihilation and trapping of singlet and triplet excitons. Values for diffusion constants and trap densities are extracted by modeling the measurements with rate equations which include singlet and triplet dynamics.

BMO authors (in alphabetic order):
Stefan Lochbrunner
Henning Marciniak
Igor Pugliesi

Order Hardcopy

WWW-Version

mailto: webmaster
Letzte Änderung: 2016-09-14 13:34