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arXiv · 1504.07163

Lattice dynamics in the paraelectric phase of PbHfO$_3$ studied by inelastic X-ray scattering

R. G. Burkovsky·D. Andronikova·Yu. Bronwald·M. Krisch·K. Roleder·A. Majchrowski·A. V. Filimonov·A. I. Rudskoy·S. B. Vakhrushev
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Abstract

We report the results of an inelastic X-ray scattering study of the lattice dynamics in the paraelectric phase of the antiferroelectric lead hafnate PbHfO$_3$. The study reveals an avoided crossing between the transverse acoustic and transverse optic phonon modes propagating along the [1 1 0] direction with [1 -1 0] polarization. The static susceptibility with respect to the generally incommensurate modulations is shown to increase on cooling for the entire $\Gamma$-M direction. We consider different approaches to the data analysis that correspond to different models for the temperature evolution of the dynamic susceptibility function. A number of similarities and differences between the lattice dynamics of PbHfO$_3$ and PbZrO$_3$ are described.

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R. G. Burkovsky, D. Andronikova, Yu. Bronwald, M. Krisch, K. Roleder, A. Majchrowski, A. V. Filimonov, A. I. Rudskoy, S. B. Vakhrushev. 2015-04-27. Lattice dynamics in the paraelectric phase of PbHfO$_3$ studied by inelastic X-ray scattering. https://doi.org/10.1088/0953-8984%2F27%2F33%2F335901

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