Influence of substrate type on transport properties of superconducting FeSe0.5Te0.5 thin films

Abstract

FeSe0.5Te0.5 thin films were grown by pulsed laser deposition on CaF2, LaAlO3 and MgO substrates and structurally and electro-magnetically characterized in order to study the influence of the substrate on their transport properties. The in-plane lattice mismatch between FeSe0.5Te0.5 bulk and the substrates shows no influence on the lattice parameters of the films, whereas the type of substrates affects the crystalline quality of the films and, therefore, the superconducting properties. The film on MgO showed an extra peak in the angular dependence of critical current density Jc(θ) at θ = 180° (H || c), which arises from c-axis defects as confirmed by transmission electron microscopy. In contrast, no Jc(θ) peaks for H || c were observed in films on CaF2 and LaAlO3. Jc(θ) can be scaled successfully for both films without c-axis correlated defects by the anisotropic Ginzburg-Landau (AGL) approach with appropriate anisotropy ratio γJ. The scaling parameter γJ is decreasing with decreasing temperature, which is different from what we observed in FeSe0.5Te0.5 films on Fe-buffered MgO substrates.

accepted for publication in SUST

References in corpus (12)

• Superconductivity at 38 K in the iron arsenide (Ba1-xKx)Fe2As2
• Superconductivity at 36 K in beta-Fe1.01Se with the compression of the interlayer separation under pressure
• The superconductivity at 18 K in LiFeAs system
• Bulk Superconductivity at 14 K in Single Crystals of Fe1+yTexSe1-x
• Systematic Comparison of Eight Substrates in the Growth of FeSe${}_{0.5}$Te${}_{0.5}$ Superconducting Thin Films
• Epitaxial growth of FeSe${}_{0.5}$Te${}_{0.5}$ thin films on CaF${}_2$ substrates with high critical current density
• Scaling behaviour of the critical current in clean epitaxial Ba(Fe1-xCox)2As2 thin films
• Control of tetrahedral coordination and superconductivity in FeSe0.5Te0.5 thin films
• Critical current scaling and anisotropy in oxypnictide superconductors
• Intrinsic pinning and the critical current scaling of clean epitaxial Fe(Se,Te) thin films
• Influenced of Fe buffer thickness on the crystalline quality and the transport properties of Fe/Ba(Fe1-xCox)2As2 bilayers
• Enhancement of Transition Temperature in FexSe0.5Te0.5 Film via Iron Vacancies

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• Superconducting properties of Ba(Fe1-xNix)2As2 thin films in high magnetic fields
• The influence of the in-plane lattice constant on the superconducting transition temperature of FeSe0.7Te0.3 thin films
• Insulator-like behavior coexisting with metallic electronic structure in strained FeSe thin films grown by molecular beam epitaxy