Time-Dependent Dielectric Susceptibility in High Electric Fields

The dielectric ac susceptibility in thin films of amorphous anodic aluminum oxide is found to be field-dependent and time-dependent. After application of a static bias field the diectric ac susceptibility increases instantly, and then relaxes logarithmically in time. The system exhibits non-linear time-variant properties but the measured changes are reversible. A model for the description of the observed effects is proposed.