Electric Fields and Currents due to Excess Charges and Dipoles in Insulators

Abstract

A general treatment is given of the relationship between internal and external parameters for a charged dielectric in a plane-parallel geometry. The charges induced on the electrodes by surface charges, volume charges, oriented dipoles in the dielectric, and an applied voltage are calculated for contacting or noncontacting electrodes. The fields outside and inside the sample are also calculated. Similarly, the external current is related to the internal conduction and depolarization currents. An analogy is developed between the current flowing through the system in short-circuit conditions and the time derivative of the applied voltage that cancels the external current. Because of its relation to the motion of carriers in the dielectric, the motion of the zero-field plane is investigated under very general conditions.