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arXiv · 0705.3732

Vogel-Fulcher freezing in relaxor ferroelectrics

R. Pirc·R. Blinc
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Abstract

A physical mechanism for the freezing of polar nanoregions (PNRs) in relaxor ferroelectrics is presented. Assuming that the activation energy for the reorientation of a cluster of PNRs scales with the mean volume of the cluster, the characteristic relaxation time $\tau$ is found to diverge as the cluster volume reaches the percolation limit. Applying the mean field theory of continuum percolation, the familiar Vogel-Fulcher equation for the temperature dependence of $\tau$ is derived.

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R. Pirc, R. Blinc. 2007-05-25. Vogel-Fulcher freezing in relaxor ferroelectrics. https://doi.org/10.1103/physrevb.76.020101

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