Noise Pulses on Transient Current during Polarization Reversal of Polyvinylidene Fluoride

Electrical noise pulses have been observed on the switching current of form-I PVDF. The pulses appeared only on the reverse current and not on the forward current against polarization. They were most intense in the initial region of polarization reversal, and their number increased with the electric field above a certain threshold field. Although the noise is very similar to the Barkhausen noise found in ferroelectric crystals, it is in fact a different type induced by a combination of remnant polarization and surface discharge. It is shown that an unfavorable arrangement of electrodes causes this type of noise to create an anomalous increase in current and a consequent serious error in determining the switching current.