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arXiv · 1210.6530

Compressible spherical dipolar glass model of relaxor ferroelectrics

R. Pirc·Z. Kutnjak·N. Novak
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Abstract

The interactions between the dielectric polarization and the fluctuations of the strain (stress) tensor in relaxor ferroelectrics are shown to give rise to the anisotropy of the anharmonic P4-term in the Landau-type free energy, however, the harmonic P2-term is still properly described by the rigid spherical random bond--random field model. These are the essential features of the compressible spherical dipolar glass model, which is used to calculate the singularities of the specific heat near field-induced critical points. The results agree with recent high-resolution calorimetric experiments in PMN [110].

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R. Pirc, Z. Kutnjak, N. Novak. 2012-10-24. Compressible spherical dipolar glass model of relaxor ferroelectrics. https://doi.org/10.1063/1.4769453

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