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Direct observation of the near-surface layer in Pb(Mg$_{1/3}$Nb$_{2/3}$)O$_{3}$ using neutron diffraction

K. Conlon·H. Luo·D. Viehland·J. F. Li·T. Whan·J. H. Fox·C. Stock·G. Shirane
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Abstract

Spatially resolved neutron diffraction as a function of crystal depth in Pb(Mg$_{1/3}$Nb$_{2/3}$)O$_{3}$ reveals the presence of a distinct near-surface region. A dramatic change in both the lattice constant and the Bragg peak intensity as a function of crystal depth is observed to occur in this region over a length scale $\sim$ 100 $μ$m. This confirms a previous assertion, based on a comparison between high-energy x-rays and neutrons, that such a near surface region exists in the relaxors. Consequences to both single crystal and powder diffraction measurements and previous bulk neutron diffraction measurements on large single crystals are discussed.

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K. Conlon, H. Luo, D. Viehland, J. F. Li, T. Whan, J. H. Fox, C. Stock, G. Shirane. 2004-07-23. Direct observation of the near-surface layer in Pb(Mg$_{1/3}$Nb$_{2/3}$)O$_{3}$ using neutron diffraction. https://doi.org/10.1103/physrevb.70.172204

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