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arXiv · 1405.0738

Charge and Spin Density Waves observed through their spatial fluctuations by coherent and simultaneous X-ray diffraction

V. L. R. Jacques·E. Pinsolle·S. Ravy·G. Abramovici·David Le Bolloc'h
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Abstract

Spatial uctuations of spin density wave (SDW) and charge density wave (CDW) in chromium have been compared by combining coherent and simultaneous X-ray diffraction experiments. Despite their close relationship, spatial fluctuations of the spin and of the charge density waves display a very different behavior: the satellite reflection associated to the charge density displays speckles while the spin one displays an impressive long-range order. This observation is hardly compatible with the commonly accepted magneto-elastic origin of CDW in chromium and is more consistent with a purely electronic scenario where CDW is the second harmonic of SDW. A BCS model taking into account a second order nesting predicts correctly the existence of a CDW and explains why the CDW is more sensitive to punctual defects.

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V. L. R. Jacques, E. Pinsolle, S. Ravy, G. Abramovici, David Le Bolloc'h. 2014-05-04. Charge and Spin Density Waves observed through their spatial fluctuations by coherent and simultaneous X-ray diffraction. https://doi.org/10.1103/physrevb.89.245127

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