Effect of injected spins with different polarized orientations on the superconductivity of La0.7Sr0.3MnO3/La1.85Sr0.15CuO4 thin films

摘要

The influence of spin-polarized quasi-particle injection on the superconductivity of epitaxial La0.7Sr0.3MnO3/La1.85Sr0.15CuO4 composite thin films is systematically investigated. Different electrode configurations on the same specimen are designed to study the role of spin injection. It is found that the upper critical field and flux pinning potential are reduced by the spin injection, especially for the field parallel to ab-plane. The manipulation of superconductivity by the spin polarization orientations of injected quasi-particles possibly originates from the different suppressions on the superconducting pairing strength, which is considered to be related to the local antiferromagnetic spin fluctuations in La1.85Sr0.15CuO4.