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arXiv · 0811.0338

Pressure-induced quenching of the charge-density-wave state observed by x-ray diffraction

Abstract

We report an x-ray diffraction study on the charge-density-wave (CDW) LaTe$_3$ and CeTe$_3$ compounds as a function of pressure. We extract the lattice constants and the CDW modulation wave-vector, and provide direct evidence for a pressure-induced quenching of the CDW phase. We observe subtle differences between the chemical and mechanical compression of the lattice. We account for these with a scenario where the effective dimensionality in these CDW systems is dependent on the type of lattice compression and has a direct impact on the degree of Fermi surface nesting and on the strength of fluctuation effects.

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A. Sacchetti, C. L. Condron, S. N. Gvasaliya, F. Pfuner, M. Lavagnini, M. Baldini, M. F. Toney, M. Merlini, M. Hanfland, J. Mesot, J. -H. Chu, I. R. Fisher, P. Postorino, L. Degiorgi. 2008-11-03. Pressure-induced quenching of the charge-density-wave state observed by x-ray diffraction. https://doi.org/10.1103/physrevb.79.201101

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