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arXiv · 1909.02482

Nanoscale phase separation and pseudogap in the hole-doped cuprates from fluctuating Cu-O-Cu bonds

Abstract

The pseudogap phenomenology is one of the enigmas of the physics of high-Tc superconductors. Many members of the cuprate family have now been characterized with high resolution in both real and momentum space, which revealed highly anisotropic Fermi arcs and local domain which break rotational symmetry in the CuO2 plane at the intraunit cell level. While most theoretical approaches to date have focused on the role of electronic correlations and doping-induced disorder to explain these features, we show that many features of the pseudogap phase can be reproduced by considering the interplay between electronic and nonlinear electron-phonon interactions within a model of fluctuating Cu-O-Cu bonds. Remarkably, we find electronic segregation arises naturally without the need to explicitly include disorder. Our approach points not only to the key role played by the oxygen bond in the pseudogap phase, but opens different directions to explore how nonequilibrium lattice excitation can be used to control the properties of the pseudogap phase.

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Sergi Julià-Farré, Alexandre Dauphin, Ravindra W. Chhajlany, Piotr T. Grochowski, Simon Wall, Maciej Lewenstein, Przemysław R. Grzybowski. 2019-09-05. Nanoscale phase separation and pseudogap in the hole-doped cuprates from fluctuating Cu-O-Cu bonds. https://doi.org/10.1103/physrevb.101.125107

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