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arXiv · 2208.08634

Prevailing charge order in overdoped cuprates beyond the superconducting dome

Qizhi Li·Hsiao-Yu Huang·Tianshuang Ren·Eugen Weschke·Lele Ju·Changwei Zou·Shilong Zhang·Qingzheng Qiu·Jiarui Liu·Shuhan Ding·Amol Singh·Oleksandr Prokhnenko·Di-Jing Huang·Ilya Esterlis·Yao Wang·Yanwu Xie·Yingying Peng
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Abstract

The extremely overdoped cuprates are generally considered to be Fermi liquid metals without exotic orders, whereas the underdoped cuprates harbor intertwined states. Contrary to this conventional wisdom, using Cu $L_3$ edge and O $K$ edge resonant x-ray scattering, we reveal a charge order (CO) in overdoped La$_{2-x}$Sr$_x$CuO$_4$ (0.35 $\leq$ x $\leq$ 0.6) beyond the superconducting dome. This CO has a periodicity of $\sim$ 6 lattice units with correlation lengths of $\sim 3 - 20$ lattice units. It shows similar in-plane momentum and polarization dependence and dispersive excitations as the CO of underdoped cuprates, but its maximum intensity differs along the c-direction and persists up to 300 K. This CO cannot be explained by either the Fermi surface instability or the doped Hubbard model and its origin remains to be understood. Our results suggest that CO is prevailing in the overdoped metallic regime and superconductivity emerges out of the CO phase upon decreasing hole carriers.

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Qizhi Li, Hsiao-Yu Huang, Tianshuang Ren, Eugen Weschke, Lele Ju, Changwei Zou, Shilong Zhang, Qingzheng Qiu, Jiarui Liu, Shuhan Ding, Amol Singh, Oleksandr Prokhnenko, Di-Jing Huang, Ilya Esterlis, Yao Wang, Yanwu Xie, Yingying Peng. 2022-10-18. Prevailing charge order in overdoped cuprates beyond the superconducting dome. https://doi.org/10.1103/physrevlett.131.116002

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