Title :
Drift of charged defects in local fields as a mechanism of degradation in ferroelectrics
Author :
Genenko, Y.A. ; Lupascu, D.C.
Author_Institution :
Darmstadt Univ. of Technol., Darmstadt
Abstract :
Two-dimensional model of point defect migration in ferroelectrics is advanced. Charge defect drift-diffusion in local depolarization fields is considered as a mechanism for aging in ferroelectrics. Numerical results are given for the coupled problems of point defect transport and electrostatic field relaxation in a 2D domain configuration. Peak values of the clamping pressure at domain walls due to space charge formation are in the range of 1divide10 MPa and the consequent coercive field is in the range of 1 kV/mm in agreement with observed coercive stresses and fields in bulk perovskite ferroelectrics.
Keywords :
ageing; barium compounds; dielectric polarisation; dielectric relaxation; electric domain walls; ferroelectric materials; point defects; space charge; BaTiO3; aging mechanism; charge defect drift-diffusion; clamping pressure; coercive field; coercive stresses; degradation mechanism; depolarization fields; domain configuration; domain walls; electrostatic field relaxation; perovskite ferroelectrics; point defect migration; space charge formation; Aging; Clamps; Degradation; Dielectric constant; Ferroelectric materials; Hysteresis; Material properties; Materials science and technology; Polarization; Space charge;
Conference_Titel :
Applications of Ferroelectrics, 2007. ISAF 2007. Sixteenth IEEE International Symposium on
Conference_Location :
Nara
Print_ISBN :
978-1-4244-1334-8
Electronic_ISBN :
1099-4734
DOI :
10.1109/ISAF.2007.4393250
