Critical behavior of the order-disorder phase transition in beta-brass investigated by x-ray scattering

Article

关键词: 2 LENGTH SCALES;    CRITICAL FLUCTUATIONS;    NEUTRON-SCATTERING;    CRITICAL-POINT;    RANGE ORDER;    TEMPERATURE;    SURFACE;    SRTIO3;   

DOI  :  10.1103/PhysRevB.94.014111

来源: SCIE

【 摘 要 】

beta-brass exhibits an archetypical example of an order-disorder transition with a critical behavior that was previously investigated by neutron scattering. The data were well described by the three-dimensional (3d) Ising model but the relatively crude experimental resolution prevented an in-depth examination of the single-length scaling hypothesis, a cornerstone in the theory of critical phenomena. With the development of synchrotron x-ray experiments, high-resolution data could be recorded and surprisingly it was found that the single-length scaling did not hold in most critical systems, possibly due to strain originating from surface defects and/or impurities. In this paper we demonstrate single-length critical behavior using high-resolution x-ray scattering in beta-brass. The investigations confirm that beta-brass behaves like a 3d Ising system over a wide range of length scales comprising correlated clusters of millions of atoms. To vary the surface sensitivity, experiments have been performed both in Bragg reflection and Laue transmission geometries but without any substantial differences observed in the scaling and critical behavior.

【 授权许可】

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