The fact that chromophores doped into a polymer self heal after photodegradation seems to contradict the
common understanding that molecular damage is a thermodynamically irreversible process. We have proposed
a model that takes into account all observations, including the kinetics of photodegradation and recovery as a
function of concentration, temperature, intensity, and sample thermal/intensity history. Correlations between
chromophores, perhaps mediated through van der Waals forces or hydrogen bonding with the polymer, appear
to actively favor the undamaged species by inducing healing in analogy to Bose-Einstein condensation. This
model is shown to predict the behavior of photo-induced decay and recovery experiments as measured with
amplified spontaneous emission and absorption spectroscopy.
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