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Soft Phonon Anomalies in Relaxor Ferroelectrics

G. Shirane·P. M. Gehring
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Abstract

A review is given of the phonon anomalies, which have been termed ``waterfalls,'' that were recently discovered through a series of neutron inelastic scattering measurements on the lead-oxide relaxor systems PZN-xPT, PMN, and PZN. We discuss a simple coupled-mode model that has been used successfully to describe the basic features of the waterfall, and which relates this unusual feature to the presence of polar micro-regions.

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G. Shirane, P. M. Gehring. 2000-11-07. Soft Phonon Anomalies in Relaxor Ferroelectrics. https://arxiv.org/abs/cond-mat/0011122

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