  The influence of an applied electric field on reversible photodegradation of
disperse orange 11 (DO11) doped into PMMA is measured using digital imaging and
conductivity measurements. Correlations between optical imaging, which measures
photodegradation and recovery, and photoconductivity enables an association to
be made between the damaged fragments and their contribution to current, thus
establishing that damaged fragments are charged species, or polarizable. Hence,
the decay and recovery process should be controllable with the applications of
an electric field. Indeed, we find that the dye polymer system is highly
sensitive to an applied electric field, which drastically affects the decay and
recovery dynamics. We demonstrate accelerated recovery when one field polarity
is applied during burning, and the opposite polarity is applied during
recovery. This work suggests that the damage threshold can be increased through
electric field conditioning; and, the results are qualitatively consistent with
the domain model of Ramini[3, 4]. The observed behavior will provide useful
input into better understanding the nature of the domains in the domain model,
making it possible to design more robust materials using common polymers and
molecular dopants.
