Interfacial-Redox-Induced Tuning of Superconductivity in YBa$_{2}$Cu$_{3}$O$_{7-{\delta}}$

TL;DR

This study demonstrates a scalable ionic approach to precisely control superconductivity in YBCO films through redox-driven oxygen migration induced by a Gd capping layer, enabling tunable superconducting transitions.

Contribution

The paper introduces a simple, scalable method for controlling superconductivity in YBCO via ionic migration, expanding the potential for interface-induced property tuning in oxides.

Findings

Complete suppression of superconductivity with sufficient Gd layer thickness.

Oxygen leaching from deep within YBCO due to Gd capping.

Superconductivity tuning achieved through redox-driven electron doping.

Abstract

Solid state ionic approaches for modifying ion distributions in getter/oxide heterostructures offer exciting potentials to control material properties. Here we report a simple, scalable approach allowing for total control of the superconducting transition in optimally doped YBa$_{2}$Cu$_{3}$O$_{7-{\delta}}$ (YBCO) films via a chemically-driven ionic migration mechanism. Using a thin Gd capping layer of up to 20 nm deposited onto 100 nm thick epitaxial YBCO films, oxygen is found to leach from deep within the YBCO. Progressive reduction of the superconducting transition is observed, with complete suppression possible for a sufficiently thick Gd layer. These effects arise from the combined impact of redox-driven electron doping and modification of the YBCO microstructure due to oxygen migration and depletion. This work demonstrates an effective ionic control of superconductivity in oxides, an interface induced effect that goes well into the quasi-bulk regime, opening up possibilities for electric field manipulation.