Universal inhomogeneous magnetic-field response in the normal state of cuprate high-Tc superconductors

TL;DR

This study reveals a universal inhomogeneous magnetic response in the normal state of various hole-doped cuprate superconductors, which scales with their maximum critical temperature and is independent of known charge or spin density wave orders.

Contribution

It demonstrates an intrinsic electronic inhomogeneity in cuprates above Tc that is not explained by known density wave orders, suggesting a fundamental property of these materials.

Findings

Inhomogeneous magnetic response extends above Tc in all studied cuprates.

The response scales with the maximum Tc of each cuprate family.

The inhomogeneity is intrinsic and not due to charge or spin density waves.

Abstract

We report the results of a muon spin rotation (muSR) study of the bulk of Bi{2+x}Sr{2-x}CaCu2O{8+\delta}, as well as pure and Ca-doped YBa2Cu3Oy, which together with prior measurements reveal a universal inhomogeneous magnetic-field response of hole-doped cuprates extending to temperatures far above the critical temperature (Tc). The primary features of our data are incompatible with the spatially inhomogeneous response being dominated by known charge density wave (CDW) and spin density wave (SDW) orders. Instead the normal-state inhomogeneous line broadening is found to scale with the maximum value Tc^max for each cuprate family, indicating it is controlled by the same energy scale as Tc. Since the degree of chemical disorder varies widely among the cuprates we have measured, the observed scaling constitutes evidence for an intrinsic electronic tendency toward inhomogeneity above Tc.