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The Significance of the Burns Temperature in Relaxor PMN

S. A. Prosandeev·S. B. Vakhrushev·N. M. Okuneva·P. A. Markovin·I. P. Raevski·I. N. Zaharchenko·M. S. Prosandeeva
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Abstract

We suggest considering the Burns temperature in lead containing relaxor ferroelectrics as the temperature, at which Pb becomes off-center and nearly randomly occupies positions around the center on a sphere with the radius, which increases with the temperature decrease. The significance of the Burns temperature, in this approach, is the crossover between the soft-mode and order-disorder dynamics. The lattice parameter, birefringence and neutron scattering experiments are analyzed in the light of this model.

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S. A. Prosandeev, S. B. Vakhrushev, N. M. Okuneva, P. A. Markovin, I. P. Raevski, I. N. Zaharchenko, M. S. Prosandeeva. 2005-06-06. The Significance of the Burns Temperature in Relaxor PMN. https://arxiv.org/abs/cond-mat/0506132

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