Cold neutron study on the diffuse scattering and phonon excitations in the relax

2020-01-30 04:10:34

diffuse order neutron scattering phonon

责任者: Hiraka, H.;Lee, S.-H.;Gehring, P.M.;Guangyong Xu;Shirane, G. 单位: Dept. of Phys., Tohoku Univ., Sendai, Japan 来源出处: Physical Review B (Condensed Matter and Materials Physics)(Phys. Rev., B, Condens, Matter Mater. Phys. (USA)),2004/11/01,70(18):184105-1 摘要: 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 Pb(Mg1/3Nb2/3)O3. We have observed a weak diffuse scattering cross section above the Burns temperature Td~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) 关键词: lead compounds;neutron diffraction;phonons;piezoelectric materials;short-range order;cold neutron scattering;diffuse scattering;phonon excitations;transverse acoustic phonons;relaxor;Burns temperature;chemical short-range order;polar nanoregions;PMN;PbMgO3NbO3