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arXiv · 1612.05068

Laser-Induced Charge-Density-Wave Transient Depinning in Chromium

V. Jacques·C. Laulhé·N. Moisan·S. Ravv·D. Le Bolloc'h
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Abstract

We report here on time-resolved x-ray diffraction measurements following femtosecond laser excitation in pure bulk chromium. Comparing the evolution of incommensurate charge-density-wave (CDW) and atomic lattice reflections, we show that, few nanoseconds after laser excitation, the CDW undergoes different structural changes than the atomic lattice. We give evidence for a transient CDW shear strain that breaks the lattice point symmetry. This strain is characteristic of sliding CDWs, as observed in other incommensurate CDW systems, suggesting the laser-induced CDW sliding capability in 3D systems. This first evidence opens perspectives for unconventional laser-assisted transport of correlated charges.

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V. Jacques, C. Laulhé, N. Moisan, S. Ravv, D. Le Bolloc'h. 2016-12-15. Laser-Induced Charge-Density-Wave Transient Depinning in Chromium. https://doi.org/10.1103/physrevlett.117.156401

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