Interstitial Iron Controlled Superconductivity in Fe1+xTe0.7Se0.3

Abstract

The superconducting series, Fe(Te,Se), has a complex structural and magnetic phase diagram that is dependent on composition and occupancy of a secondary interstitial Fe site. In this letter, we show that superconductivity in Fe1+xTe0.7Se0.3 can be enhanced by topotactic deintercalation of the interstitial iron, demonstrating the competing roles of the two iron sites. Neutron diffraction reveals a flattening of the Fe(Te,Se)4 tetrahedron on Fe removal of iron and an increase in negative thermal expansion within the ab plane that correlates with increased lattice strain. Inelastic neutron scattering shows that a gapped excitation at 6 meV, evolves into gapless paramagnetic scattering with increasing iron; similar to the fluctuations observed for non-superconducting Fe1+xTe itself.

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Cited by in corpus (32)

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• Review of annealing effects and superconductivity in Fe${}_{1+y}$Te${}_{1-x}$Se${}_x$ superconductors
• The intercalation chemistry of layered iron chalcogenide superconductors
• Annealing, acid, and alcoholic beverage effects on Fe1+yTe0.6Se0.4
• The magnetic and structural properties near the Lifshitz point in Fe1+xTe
• Friedel-like Oscillations from Interstitial Iron in Superconducting Fe1+yTe0.62Se0.38
• Superconductivity and magnetism in Iron Sulfides Intercalated by Metal Hydroxides
• Influence of interstitial Fe to the phase diagram of Fe${}_{1+y}$Te${}_{1-x}$Se${}_x$ single crystals
• Large, Homogeneous, and Isotropic Critical Current Density in Oxygen-Annealed Fe1+yTe0.6Se0.4 Single Crystal
• Soft striped magnetic fluctuations competing with superconductivity in Fe_{1+x}Te
• The magnetic and electronic properties of Oxyselenides - influence of transition metal ions and lanthanides
• Inhomogeneous superconductivity induced by interstitial Fe deintercalation in oxidizing-agent-annealed and HNO3-treated Fe1+y(Te1-xSex)
• Coupling of electronic and magnetic properties in Fe1+y(Te1-xSex)
• Bulk Superconductivity in Fe1+yTe0.6Se0.4 Induced by Removal of Excess Fe
• Spin fluctuations and superconductivity in powders of Fe_1+xTe_0.7Se_0.3 as a function of interstitial iron concentration
• Effect of Vacuum Annealing on Superconductivity in Fe(Se,Te) Single Crystals
• Chalcogen Height Dependence of Magnetism and Fermiology in FeTe_xSe_{1-x}
• Mössbauer study of the '11' iron-based superconductors parent compound Fe(1+x)Te
• Competing spin density wave, collinear, and helical magnetism in Fe1+xTe
• Common origin of the two types of magnetic fluctuations in iron chalcogenides
• Synthesis, phase stability, structural and physical properties of 11-type iron chalcogenides
• Coexistence of superconductivity and short-range double-stripe spin correlations in Te-vapor annealed FeTe${}_{1-x}$Se${}_x$ with $x\le 0.2$
• Structure and Magnetism in the Bond Frustrated Spinel, ZnCr2Se4
• Role of interstitial "caged" Fe in the superconductivity of FeTe1/2Se1/2
• Sulfur annealing effect for superconductivity in iron chalcogenide compounds
• Size Dependence of Oxygen-annealing Effects on Superconductivity of Fe{1+y}Te{1-x}S{x}
• A flat band at the chemical potential of a Fe1.03Te0.94S0.06 superconductor observed by angle-resolved photoemission spectroscopy
• Magnetic surface reconstruction in the van-der-Waals antiferromagnet Fe${}_{1+x}$Te
• Band Engineering of Dirac cones in Iron Chalcogenides
• Acoustic lattice instabilities at the magneto-structural transition in Fe${}_{1.057(7)}$Te