Dynamics and optical absorption of electronic excitations under the influence of coloured noise

For a model dimer the influence of vibrational degrees of freedom on electronic excitations is described by a dichotomic Markov process with coloured noise. Within this model the energy transport between the two units of the dimer, especially the transition between coherent and incoherent motion is discussed. Furthermore the optical absorption line shape is evaluated for various values of the model parameters

Photo- and Electroproduction of Eta Mesons

Eta photo- and electroproduction off the nucleon is investigated in an effective lagrangian approach that contains Born terms and both vector meson and nucleon resonance contributions. In particular, we review and develop the formalism for coincidence experiments with polarization degrees of freedom. The different response functions appearing in single and double polarization experiments have been studied. We will present calculations for structure functions and kinematical conditions that are most sensitive to details of the lagrangian, in particular with regard to contributions of nucleon resonances beyond the dominant $S_{11}$(1535) resonance.Comment: 24 pages RevTeX/LaTeX2.09, NFSS1, 13 figures (in separate file (tar,gzip and uue)), accepted for publication in Z. Phys.

Dynamics and spectroscopy of electronic excitations in molecular aggregates

The influence of vibrational degrees of freedom on electronic excitations for a model dimer is described by a dichotomic Markov process with coloured noise. For this model the transport of the excitation between the two units of the dimer and especially the transition between coherent and incoherent motion is discussed. Furthermore the optical absorption line shape is evaluated for various values of the model parameters

Simulation of excitonic optical line shapes of cyclic oligomers - models for basic units of photosynthetic antenna systems: transfer integral versus local energy fluctuations with dichotomic coloured noise

The support of the Deutscher Akademischer Austaschdienst (DAAD), of the Volkswagen Foundation and of the Deutsche Forschungmeinschaft (SFB 239) are gratefully acknowledgedConsiglio Nazionale delle Ricerche (CNR). Biblioteca Centrale / CNR - Consiglio Nazionale delle RichercheSIGLEITItal