High-pressure studies of optical dephasing in polymer glasses.
The effect of high pressure on the optical dephasing of chromophores in organic polymers at low temperature is evaluated within the stochastic sudden jump two-level-system (TLS) model. The approximations within the "standard" TLS model cannot account for the observed pressure dependence of the pure dephasing rate without ad hoc assumptions about changes in the TLS density of states. However, the photon echo model of Geva and Skinner for disordered systems can be used to model pressure-dependent optical dephasing results for a variety of doped polymer systems without assuming changes in the TLS density of states. The relative importance of pressure-induced changes in TLS density, chromophore-TLS coupling, and TLS-phonon coupling is evaluated by fitting experimental high-pressure photon echo results to the TLS model.
McIntire
Michael J
MJ
Department of Chemistry, Natural and Applied Sciences, University of Wisconsin-Green Bay, Green Bay, Wisconsin 54311, USA.
Yamaguchi
Masashi
M
Kol'chenko
Misha A
MA
Vainer
Yuri G
YG
Chronister
Eric L
EL