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arXiv · 1612.04105

Experimental Evidences for Static Charge Density Waves in Iron Oxy-pnictides

A. Martinelli·P. Manfrinetti·A. Provino·A. Genovese·F. Caglieris·G. Lamura·C. Ritter·M. Putti
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Abstract

In this Letter we report high-resolution synchrotron X-ray powder diffraction and transmission electron microscope analysis of Mn-substituted LaFeAsO samples, demonstrating that a static incommensurate modulated structure develops across the low-temperature orthorhombic phase, whose modulation wave-vector depends on the Mn content. The incommensurate structural distortion is likely originating from a charge-density-wave instability, a periodic modulation of the density of conduction electrons associated with a modulation of the atomic positions. Our results add a new component in the physics of Fe-based superconductors, indicating that the density wave ordering is charge-driven.

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A. Martinelli, P. Manfrinetti, A. Provino, A. Genovese, F. Caglieris, G. Lamura, C. Ritter, M. Putti. 2016-12-13. Experimental Evidences for Static Charge Density Waves in Iron Oxy-pnictides. https://doi.org/10.1103/physrevlett.118.055701

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