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X-ray scattering study of two length scales in the critical fluctuations of CuGeO3

Y. J. Wang·Y. -J. Kim·R. J. Christianson·S. C. LaMarra·F. C. Chou·R. J. Birgeneau
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Abstract

The critical fluctuations of CuGeO$_3$ have been measured by synchrotron x-ray scattering, and two length scales are clearly observed. The ratio between the two length scales is found to be significantly different along the $a$ axis, with the $a$ axis along the surface normal direction. We believe that such a directional preference is a clear sign that surface random strains, especially those caused by dislocations, are the origin of the long length scale fluctuations.

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Y. J. Wang, Y. -J. Kim, R. J. Christianson, S. C. LaMarra, F. C. Chou, R. J. Birgeneau. 2000-04-20. X-ray scattering study of two length scales in the critical fluctuations of CuGeO3. https://doi.org/10.1103/physrevb.63.052502

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