Fluorescence changes of dyes in amorphous solids, induced by selective laser excitation and by heat pulses

Phonon-induced fluorescence changes have been obtained in the shape of the spectra of selectively laser-excited dye molecules in noncrystalline organic solids, e.g. perylene molecules in Langmuir films of Cd arachidate. The changes in the zero-phonon lines and in the sidebands are observed after heat pulse irradiation (phonon memory), and by realtime phonon detection. The results are explained by electron-phonon interaction and by the model of matrix-shift variations caused by phonon-induced transitions in two-level systems in amorphous solids. (orig.)