Thermodynamic phase diagram of the competition between superconductivity and charge order in cuprates

Giulia Venditti; Ilaria Maccari; Jose Lorenzana; Sergio Caprara

doi:10.21468/scipostphys.15.6.230

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arXiv · 2306.17094

Thermodynamic phase diagram of the competition between superconductivity and charge order in cuprates

Giulia Venditti·Ilaria Maccari·Jose Lorenzana·Sergio Caprara

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Abstract

We argue that there is a special doping point in the phase diagram of cuprates, such that the condensation of holes into a charge-ordered and into a superconducting phase are degenerate in energy but with an energy barrier in between. We present a Monte Carlo simulation of this problem without and with quenched disorder. While in the clean case charge order and superconductivity are separated by a first-order line which is nearly independent of temperature, in the presence of quenched disorder, charge order is fragmented into domains separated by superconducting filaments reminiscent of the supersolid behavior in $^4$He. The resulting phase diagram is in good agreement with the experiments.

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Giulia Venditti, Ilaria Maccari, Jose Lorenzana, Sergio Caprara. 2023-06-29. Thermodynamic phase diagram of the competition between superconductivity and charge order in cuprates. https://doi.org/10.21468/scipostphys.15.6.230

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