Dresden 2011 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

DF: Fachverband Dielektrische Festkörper

DF 12: Poster

DF 12.2: Poster

Mittwoch, 16. März 2011, 15:00–17:30, P1

Polarisation switching dynamics by Inhomogeneous Field Mechanism in ferroelectric polymers — •Jörg Schütrumpf, Sergej Zhukov, Yuri Genenko, and Heinz von Seggern — Technische Universität Darmstadt, Darmstadt, Deutschland

The temporal behaviour of polarisation reversal in ferroelectric polymers like Polyvinylidene Fluoride (PVDF) cannot be satisfactory explained by simple models such as the classical Kolmogorov-Avrami-Ishibashi model for ferroelectric ceramics or by models considering stretched exponential laws. In the present contribution the Inhomogeneous Field Mechanism model recently proposed for PZT ceramics has been applied to polymer ferroelectrics for the first time. The model is based on the assumption that the switching volume is divided into many regions with independent dynamics, only determined by the local electric field. The local field values are randomly distributed over the ensemble of regions due to intrinsic inhomogeneities of the material. Therefore an inhomogeneous switching behaviour is induced by the varying local fields of each region. The electric field distribution can be directly extracted from the experimental data. The model satisfactory describes virgin and fatigued samples over a broad time-field domain covering nine orders of magnitude of the poling time and electric field values from 50-200 kV/mm. In the same way we can conclude that the IFM model is adaptive to ferroelectric ceramics and semi-crystalline polymers at once.