Accession Number : ADP008233

Title :   Photon Echo and Time-Resolved Fluorescence Anisotropy Measurements of Organically Doped Sol-Gel Glasses,

Corporate Author : CALIFORNIA UNIV RIVERSIDE DEPT OF CHEMISTRY

Personal Author(s) : L'Esperance, Drew M. ; Crowell, Robert A. ; Chronister, Eric L.

Report Date : 22 MAY 1992

Pagination or Media Count : 3

Abstract : We present time resolved measurements of homogeneous dephasing of organic dopants in inorganic sol-gel glasses. A variety of organically doped sol-gel glasses have been synthesized and their dynamics investigated by time-resolved photon echo and fluorescence anisotropy measurements. The homogeneous dephasing rate of the chromophore is determined from photon echo measurements at low temperature (T = 1.4 K), while thermally activated homogeneous dephasing mechanisms are investigated by temperature dependent photon echo measurements. Our results are contrasted with recent hole-burning experiments on doped sol-gel glasses. Aluminosilicate (ASE) and tetraethoxy silane (TEOS) glasses have been doped with rhodamine dyes, polyaromatics, cresylviolet, resorufin and a wide range of chromophores with different nonradiative electronic relaxation rates. A small list includes naphthalene (170ns), rhodamine 6G (2ns), Rose Bengal (500ps), stilbene (70ps), azulene (2ps), as well as quinizarin and chlorin. The visible absorption spectra of some organically doped sol-gel glasses is shown. The low temperature homogeneous dephasing rate for chromophores doped into TEOS and in ASE sol-gel glasses has been measured utilizing photon echo measurements.

Descriptors :   *ECHOES, *PHOTONS, *GLASS, ABSORPTION SPECTRA, ANISOTROPY, AZULENES, CHROMOPHORES, DYES, FLUORESCENCE, GELS, LOW TEMPERATURE, MEASUREMENT, NAPHTHALENES, RELAXATION, SILANES, SPECTRA, STILBENES, TEMPERATURE, DOPING, VISIBLE SPECTRA, MATRIX MATERIALS, MOLECULAR SPECTROSCOPY.

Subject Categories : Ceramics, Refractories and Glass
      Atomic and Molecular Physics and Spectroscopy

Distribution Statement : APPROVED FOR PUBLIC RELEASE