A model of long time decay of space charge in polymers

The basic processes determining the time evolution of current carriers allow one to predict the observed phenomenon of a very slow decay of implanted charge. According to the model presented here, the charge decay takes place in two distinct stages: the first is rapid but the second slow and linear, whereas the conductivity evolution takes place in three stages. In the first stage one observes a sudden decrease of conductivity; in the second its slow recovery, and in the third stage, when the source of electric field no longer exists, one observes more rapid, close to exponential, return to the equilibrium value