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X-Ray Scattering Evidence for Macroscopic Strong Pinning Centers in the Sliding CDW state of NbSe_3

D. Rideau·P. Monceau·R. Currat·H. Requardt·F. Nad·J. E. Lorenzo·S. Brazovskii·C. Detlefs·G. Grubel
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Abstract

Using high-resolution X-ray scattering techniques, we measure the variation, q(x), of the position in reciprocal space of the CDW satellite, in the sliding state, along the length of NbSe_3 whiskers. We show that structural defects and intentionally X-ray radiation-damaged regions increase locally the CDW pinning force, and induce CDW phase distortions which are consistent with those observed near contacts. Using the semi-microscopic model from Brazovskii describing the normal-condensed carrier conversion, with spatially varying parameters, we account for the experimental spatial dependence of the CDW phase gradient near both types of defects.

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D. Rideau, P. Monceau, R. Currat, H. Requardt, F. Nad, J. E. Lorenzo, S. Brazovskii, C. Detlefs, G. Grubel. 2000-08-07. X-Ray Scattering Evidence for Macroscopic Strong Pinning Centers in the Sliding CDW state of NbSe_3. https://doi.org/10.1209/epl%2Fi2001-00608-x

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