Direct observation of the near-surface layer in Pb ( Mg 1 ∕ 3 Nb 2 ∕ 3 ) O 3 using neutron diffraction

摘要: Spatially resolved neutron diffraction as a function of crystal depth in $\mathrm{Pb}({\mathrm{Mg}}_{1∕3}{\mathrm{Nb}}_{2∕3}){\mathrm{O}}_{3}$ reveals the presence distinct near-surface region where strong distortion lattice exists. A dramatic change both constant and Bragg peak intensity is observed to occur this over length scale $\ensuremath{\sim}100\phantom{\rule{0.3em}{0ex}}\ensuremath{\mu}\mathrm{m}$. This confirms previous assertion, based on comparison between high-energy x rays neutrons, that such near surface exists relaxors. Consequences single powder measurements bulk large crystals are discussed.