Abstract

Most work on the electronic dephasing of molecules in the condensed phase has concerned either liquids at room temperature [1]. or organic solids at very low temperatures (< 15 K) [2]. In this work we study the dephasing of the molecules LD690 in the polymers PMMA and PVA and LDS750 in PMMA in the intermediate temperature range 300-30 K. We find that the observed dephasing rate for LD690 is strongly temperature-dependent in both polymers, while that of LDS750 changes only slightly with temperature. LDS750 is known to undergo a large change i n charge distribution and fast Stokes shift upon excitation [3], unlike LD690, and the nature of its coupling to the bath is thus very different from that of LD690.

© 1996 Optical Society of America