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Electric Field Effects on the Diffuse Scattering in PZN-8%PT

P. M. Gehring·K. Ohwada·G. Shirane
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Abstract

We report measurements of the neutron diffuse scattering from a single crystal of the relaxor ferroelectric Pb(Zn_1/3Nb_2/3)O_3 doped with 8% PbTiO_3 (PZN-8%PT) for temperatures 100 K < T < 530 K and electric fields 0 kV/cm < E < 10 kV/cm. The diffuse scattering is strongly suppressed transverse to the (003) Bragg peak at 400 K for E = 2 kV/cm applied along the [001] direction. However, no change in the diffuse scattering is observed transverse to (300), even for field strengths up to 10 kV/cm. Thus the application of an external electric field in the tetragonal phase does not produce a macroscopically polarized state. This unusual behavior can be understood within the context of the Hirota et al. phase-shifted polar nanoregion (PNR) model of the relaxor diffuse scattering, since an electric field E oriented parallel to [001] would remove the shift of the nanoregions along [001] while preserving those along the orthogonal [100] direction.

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P. M. Gehring, K. Ohwada, G. Shirane. 2003-07-27. Electric Field Effects on the Diffuse Scattering in PZN-8%PT. https://doi.org/10.1103/physrevb.70.014110

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