| Autor: |
Ganesh, P., Cockayne, E., Ahart, M., Cohen, R. E., Burton, B., Hemley, R. J., Ren, Yang, Yang, Wenge, Ye, Z-G |
| Rok vydání: |
2009 |
| Předmět: |
|
| Druh dokumentu: |
Working Paper |
| DOI: |
10.1103/PhysRevB.81.144102 |
| Popis: |
High-pressure and variable temperature single crystal synchrotron X-ray measurements combined with first-principles based molecular dynamics simulations study diffuse scattering in the relaxor ferroelectric system PSN (PbSc$_{1/2}$Nb$_{1/2}$O$_3$). Constant temperature experiments show pressure induced transition to the relaxor phase at different temperatures characterized by butterfly and rod shaped diffuse scattering around the $\{$h00$\}$ and $\{$hh0$\}$ Bragg spots, respectively. The simulations reproduce the observed diffuse scattering features as well as their pressure-temperature behavior, and show that they arise from polarization correlations between chemically-ordered regions, which in previous simulations were shown to behave as polar nanoregions. Simulations also exhibit radial diffuse scattering (elongated towards and away from {\bf Q}=(000)), that persists even in the paraelectric phase, consistent with previous neutron experiments on (PbMg$_{1/3}$Nb$_{2/3}$O$_3$) (PMN) |
| Databáze: |
arXiv |
| Externí odkaz: |
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