Phase Separation and Chemical Inhomogeneity in the Iron Chalcogenide Superconductor Fe1+yTexSe1-x

Abstract

We report investigation on Fe1+yTexSe1-x single crystals by using scanning transmission electron microscopy (STEM) and electron energy loss spectroscopy (EELS). Both nonsuperconducting samples with excess iron and superconducting samples demonstrate nanoscale phase separation and chemical inhomogeneity of Te/Se content, which we attribute to a miscibility gap. The line scan EELS technique indicates ~20% or less fluctuation of Te concentration from the nominal compositions.

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Cited by in corpus (13)

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• Interplay between magnetism and superconductivity in iron-chalcogenide superconductors: crystal growth and characterizations
• Temperature and time scaling of the peak-effect vortex configuration in FeTe${}_{0.7}$Se${}_{0.3}$
• The phase diagrams of iron-based superconductors: theory and experiments
• Microstructural magnetic phases in superconducting FeTe0.65Se0.35
• Coupling of electronic and magnetic properties in Fe1+y(Te1-xSex)
• Thermal evolution of antiferromagnetic correlations and tetrahedral bond angles in superconducting FeTe${}_{1-x}$Se${}_x$
• Common origin of the two types of magnetic fluctuations in iron chalcogenides
• Coexistence of superconductivity and short-range double-stripe spin correlations in Te-vapor annealed FeTe${}_{1-x}$Se${}_x$ with $x\le 0.2$
• Magnetic glassy phase in FeSeTe single crystals
• Nano-scale Inhomogeneous Superconductivity in Fe(Te1-xSex) Probed by Nanostructure-transport
• Magnetic neutron scattering studies on the Fe-based superconductor system Fe${}_{1+y}$Te${}_{1-x}$Se${}_x$
• Thickness-induced crossover from strong to weak collective pinning in exfoliated FeTe${}_{0.6}$Se${}_{0.4}$ thin films at 1 T