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arXiv · 1707.04367

On Nematicity and Charge Order in Superoxygenated La$_{2-x}$Sr$_x$CuO$_{4+y}$

Zhiwei Zhang·R. Sutarto·F. He·F. C. Chou·L. Udby·S. L. Holm·Z. H. Zhu·W. A. Hines·J. I. Budnick·B. O. Wells
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Abstract

A nematic order in stripe-ordered cuprates was recently identified with (001) reflection at resonant energies associated with the in-plane states. However, whether this resonant reflection is ubiquitous among all 214 cuprates is still unknown. Here we report a Resonant soft X-ray Scattering (RXS) measurement on two La$_{2-x}$Sr$_x$CuO$_{4+y}$ crystals. Charge order was found in La$_2$CuO$_{4+y}$ with a total hole concentration near 0.125/Cu but no measurable (001) peak at any resonance, while in a La$_{1.94}$Sr$_{0.06}$CuO$_{4+y}$ sample near 0.16/Cu a (001) peak resonant was identified to be consistent with the presence of LTT tilting. The lack of such a (001) peak in a compound with stripe-like charge order raises questions about nematicity and the origin of the scattering feature.

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Zhiwei Zhang, R. Sutarto, F. He, F. C. Chou, L. Udby, S. L. Holm, Z. H. Zhu, W. A. Hines, J. I. Budnick, B. O. Wells. 2017-07-14. On Nematicity and Charge Order in Superoxygenated La$_{2-x}$Sr$_x$CuO$_{4+y}$. https://doi.org/10.1103/physrevlett.121.067602

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