Unusual behavior of cuprates explained by heterogeneous charge localization

Abstract

The discovery of high-temperature superconductivity in cuprates ranks among the major scientific milestones ofthe past half century, yet pivotal questions regarding the complex phase diagram of these materials remain un-answered. Generally thought of as doped charge-transfer insulators, these complex oxides exhibit pseudogap,strange-metal, superconducting, and Fermi liquid behavior with increasing hole-dopant concentration. Motivatedby recent experimental observations, here we introduce a phenomenological model wherein exactly one hole perplanar copper-oxygen unit is delocalized with increasing doping and temperature. The model is percolative innature, with parameters that are highly consistent with experiments. It comprehensively captures key un-conventional experimental results, including the temperature and the doping dependence of the pseudogap pheno-menon, the strange-metal linear temperature dependence of the planar resistivity, and the doping dependence of thesuperfluid density. The success and simplicity of the model greatly demystify the cuprate phase diagram and point to alocal superconducting pairing mechanism.