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arXiv · 1905.02436

Quasiparticle interference and charge order in a heavily overdoped non-superconducting cuprate

Abstract

One of the key issues in unraveling the mystery of high Tc superconductivity in the cuprates is to understand the normal state outside the superconducting dome. Here we perform scanning tunneling microscopy and spectroscopy measurements on a heavily overdoped, non-superconducting (Bi,Pb)2Sr2CuO6+x cuprate. Spectroscopic imaging reveals dispersive quasiparticle interferences and the Fourier transforms uncover the evolution of momentum space topology. More interestingly, we observe nanoscale patches of static charge order with sqrt(2)*sqrt(2) periodicity. Both the dispersive quasiparticle interference and static charge order can be qualitatively explained by theoretical calculations, which reveal the unique electronic structure of strongly overdoped cuprate.

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Xintong Li, Ying Ding, Chaocheng He, Wei Ruan, Peng Cai, Cun Ye, Zhenqi Hao, Lin Zhao, Xingjiang Zhou, Qianghua Wang, Yayu Wang. 2019-05-07. Quasiparticle interference and charge order in a heavily overdoped non-superconducting cuprate. https://doi.org/10.1088/1367-2630/aacb5e

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