Author/Authors :
Jundt، نويسنده , , C. and Klein، نويسنده , , G. and Sipp، نويسنده , , B. and Le Moigne، نويسنده , , J. and Joucla، نويسنده , , M. and Villaeys، نويسنده , , A.A.، نويسنده ,
Abstract :
Pentacene microcrystalline thin films have been investigated by pump-probe spectroscopy in the femtosecond regime. The competition between induced absorption in the singlet S1 → Sn and triplet T1 → Tn excited electronic configurations and bleaching of the S0 → S1 transition has been observed. A theoretical description is proposed to explain the experimental results. The importance of the different contributions associated with the various competing processes are stressed. A very fast triplet exciton creation with rate constant 1.3 × 1013 s−1 is attributed to a fission process from one S1 exciton to a pair of lowest triplet T1 excitons.
