TEMPERATURE-DEPENDENT OPTICAL DEPHASING IN SOL-GEL GLASSES - PHOTON-ECHO MEASUREMENTS OF RHODAMINE-101 AND QUINIZARIN DOPED ALUMINOSILICA XEROGELS

Temperature-dependent (1.2-2.1 K) photon echo measurements have been p erformed on quinizarin and rhodamine 101 doped into aluminosilica sol- gel glasses as well as rhodamine 101 doped poly-methyl-methacrylate (P MMA) polymer. We observe a temperature-dependent homogeneous linewidth for both quinizarin and rhodamine in the aluminosilica xerogel (ASX) matrix proportional to T-2, in contrast to the T-1.3+/-0.1 linewidth d ependence typically observed for a variety of organic and inorganic gl ass hosts in this temperature range (including rhodamine 101 doped PMM A). The contrasting optical dephasing results for the ASX glass and PM MA suggest that the ASX glass may have unique two-level-system dynamic s. (C) 1995 American Institute of Physics.