Reversible shift in the superconducting transition for La1.85Sr0.15CuO4 and BaFe1.8Co0.2As2 using piezoelectric substrates

TL;DR

This study demonstrates that applying small, reversible biaxial strains via piezoelectric substrates can modulate the superconducting transition temperatures in La1.85Sr0.15CuO4 and BaFe1.8Co0.2As2 thin films, revealing strain-sensitive superconducting properties.

Contribution

It extends the use of piezoelectric substrates to iron arsenic superconductors, showing reversible strain effects on their superconducting transitions for the first time.

Findings

Reversible shift of 0.44 K in La1.85Sr0.15CuO4

Reversible shift of 0.2 K in BaFe1.8Co0.2As2

Strain of approximately 0.02% induces measurable superconducting changes

Abstract

The use of piezoelectric substrates enables a dynamic observation of strain dependent properties of functional materials. Based on studies with La1.85Sr0.15CuO4 we extended this approach to the iron arsenic superconductors represented by BaFe2-xCoxAs2 to investigate strain driven changes in detail. We demonstrate that epitaxial thin films can be prepared on (001)Pb(Mg1/3Nb2/3)0.72Ti0.28O3 substrates using pulsed laser deposition. The structural as well as the electric properties of the grown films were characterized in detail. A reversible shift of the superconducting transition of 0.44 K for La1.85Sr0.15CuO4 and 0.2 K for BaFe1.8Co0.2As2 was observed applying a biaxial strain of 0.022% and 0.017% respectively.