Inhomogeneous Magnetic-Field Response of YBa2Cu3Oy and La2-xSrxCuO4 Persisting above the Bulk Superconducting Transition Temperature

TL;DR

This study reveals that in YBa2Cu3Oy and La2-xSrxCuO4, an inhomogeneous magnetic response persists well above the superconducting transition temperature, indicating a possible link to superconductivity even in the normal state.

Contribution

It demonstrates the existence of spatially inhomogeneous magnetic responses above Tc in cuprates, suggesting a coupling to superconducting properties.

Findings

Inhomogeneous magnetic response persists above Tc.

Response correlates with doping and superconducting carrier density.

Observed even in highly ordered YBa2Cu3O6.50.

Abstract

We report that in YBa2Cu3Oy and La2-xSrxCuO4 there is a spatially inhomogeneous response to magnetic field for temperatures T extending well above the bulk superconducting transition temperature Tc. An inhomogeneous magnetic response is observed above Tc even in ortho-II YBa2Cu3O6.50, which has highly ordered doping. The degree of the field inhomogeneity above Tc tracks the hole doping dependences of both Tc and the density of the superconducting carriers below Tc, and therefore is apparently coupled to superconductivity.