Correlations between charge ordering and local magnetic fields in overdoped YBa2Cu3O6+x

Zero-field muon spin-relaxation (ZF-μSR) measurements were undertaken on under- and overdoped samples of superconducting YBa2Cu3O6+x to determine the origin of the weak static magnetism recently reported in this system. The temperature dependence of the muon spin-relaxation rate in overdoped crystals displays an unusual behavior in the superconducting state. A comparison to the results of NQR and lattice structure experiments on highly doped samples provides compelling evidence for strong coupling of charge, spin, and structural inhomogeneities.