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】

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