Influence of conductivity on the dynamics of poling and short circuiting in poly(vinylidene fluoride)

It has been verified experimentally that the value of the back switched ferroelectric polarization in PVDF during short circuiting depends on the preceding poling time, as was predicted earlier by analyzing a model suggested for initial poling. The back switched polarization exhibits a maximum in samples poled for about 100 /spl mu/s, while it decreases to zero for much shorter and much longer poling times. The experimentally found build-up of a slow polarization component, as well as the high stability of polarization in long time poled PVDF are explained by the charge accumulation at the interfacial boundaries between ferroelectric and non-ferroelectric components of PVDF due to a finite conductivity. The suggested model is applicable for all two-component ferroelectrics.