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Cold neutron scattering study on diffuse and phonon excitations in the relaxor PbMg(1/3)Nb(2/3)O3

H. Hiraka·S. -H. Lee·P. M. Gehring·Guangyong Xu·G. Shirane
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Abstract

Cold neutron scattering experiments have been performed to explore the energy, temperature, and wave-vector dependence of the diffuse scattering and the transverse acoustic (TA) phonons in the relaxor PbMg(1/3)Nb(2/3)O3. We have observed a weak, but definitive, diffuse scattering cross section above the Burns temperature T_d ~ 600 K. This cross section, which is most likely caused by chemical short-range order, persists down to 100 K, and coexists with the much stronger diffuse scattering that is attributed to the polar nanoregions. A systematic study of the TA phonon around (1, 1, 0) has also been carried out. The phonon is well defined for small wave vectors q, but broadens markedly around q = (0.1, -0.1, 0).

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H. Hiraka, S. -H. Lee, P. M. Gehring, Guangyong Xu, G. Shirane. 2004-03-23. Cold neutron scattering study on diffuse and phonon excitations in the relaxor PbMg(1/3)Nb(2/3)O3. https://doi.org/10.1103/physrevb.70.184105

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