Site-Selective Excitation Spectroscopy of Dye-doped Inorganic Amorphous Hosts Prepared by Sol-Gel Method

Dye-doped inorganic glasses prepared by a sol-gel method have received much interest during the last decade, especially for the application of optical media such as solid-state dye lasers and high-density optical memories.1-3 In order to obtain a preferable combination of host matrices and guest molecules for optical applications, it is important to know precisely about the electron-phonon interaction of the host-guest system. So far, we have experimentally determined the Debye-Waller factor, the site energy distribution function, and the density of states of low-frequency host vibrational modes weighted by the electron-phonon coupling strength in porphyrindoped polymers using a resonance fluorescence technique.4,5 In this study, sol-gel inorganic matrices, SiO2 and SiO2-TiO2, are examined using a similar method by employing a cationic laser dye, oxazine 4 perchlorate(ox4), as the optical center.