Ordering fluctuation dynamics in AuAgZn2 | |
Article | |
关键词: X-RAY; CRITICAL EXPONENTS; FE-AL; SPECTROSCOPY; DIFFRACTION; SERIES; FE3AL; MODEL; | |
DOI : 10.1103/PhysRevB.92.094102 | |
来源: SCIE |
【 摘 要 】
The second-order ordering transition of the AuAgZn2 alloy has been studied by coherent x-ray scattering. Within a few degrees above the critical temperature T-c, equilibrium critical fluctuations are observed together with some pretransitional local ordering connected to sample defects. The speckles observed correspond to heterodyne interference between local ordering and fluctuations and show a mixed static and dynamical behavior in a narrow domain of a few tenths of degree above Tc. The dynamical behavior is shown to correspond to the critical slowing down of the fluctuations in the vicinity of the transition (model A of Hohenberg and Halperin [ Rev. Mod. Phys. 49, 435 (1977)]). A rough comparison can be carried out with the classical diffusion models. Some improvements of the method are discussed.
【 授权许可】
Free