Disappearance of static magnetic order and evolution of spin fluctuations in Fe${}_{1+\delta }$Se${}_x$Te${}_{1-x}$

Abstract

We report neutron scattering studies on static magnetic orders and spin excitations in the Fe-based chalcogenide system Fe${}_{1+\delta }$Se${}_x$Te${}_{1-x}$ with different Fe and Se compositions. Short-range static magnetic order with the "bicollinear" spin configuration is found in all non-superconducting samples, with strong low-energy magnetic excitations near the $(0.5,0)$ in-plane wave-vector (using the two-Fe unit cell) for Se doping up to 45%. When the static order disappears and bulk superconductivity emerges, the spectral weight of the magnetic excitations shifts to the region of reciprocal space near the in-plane wave-vector $(0.5,0.5)$, corresponding to the "collinear" spin configuration. Our results suggest that spin fluctuations associated with the collinear magnetic structure appear to be universal in all Fe-based superconductors, and there is a strong correlation between superconductivity and the character of the magnetic order/fluctuations in

6 pages, 5 figures, 1 table

References in corpus (20)

• Magnetic Order versus superconductivity in the Iron-based layered La(O1-xFx)FeAs systems
• Superconductivity at 43 K in Samarium-arsenide Oxides $SmFeAs{O}_{1-x}{F}_x$
• Structural and magnetic phase diagram of CeFeAsO1-xFx and its relationship to high-temperature superconductivity
• Extreme Sensitivity of Superconductivity to Stoichiometry in FeSe (Fe1+dSe)
• Tellurium substitution effect on superconductivity of the alpha-phase Iron Selenide
• Incommensurate magnetic order in the alpha-Fe(Te,Se) superconductor systems
• Effect of Structural Parameters on Superconductivity in Fluorine-Free LnFeAsO1-y (Ln=La,Nd)
• First-order magnetic and structural phase transitions in Fe${}_{1+y}$Se${}_x$Te${}_{1-x}$
• The Structural Phase Transition in FeSe (Fe1+dSe)
• Coexistence of the spin-density-wave and superconductivity in the (Ba,K)Fe2As2
• From (pi, 0) magnetic order to superconductivity with (pi, pi) magnetic resonance in Fe1.02(Te1-xSex)
• Two-dimensional resonant magnetic excitation in BaFe1.84Co0.16As2
• Spin Gap and Resonance at the Nesting Wavevector in Superconducting FeSe0.4Te0.6
• Unified Picture for Magnetic Correlations in Iron-Based Superconductors
• Three-dimensional Resonance in superconducting BaFe${}_{1.9}$Ni${}_{0.1}$As${}_2$
• Lattice and Magnetic structures of PrFeAsO, PrFeAsO0.85F0.15 and PrFeAsO0.85
• Doping evoluton of antiferromagnetic order and structural distortion in LaFeAsO${}_{1-x}$F${}_x$
• Testing the itinerancy of spin dynamics in superconducting Bi2212
• Short-range incommensurate magnetic order near the superconducting phase boundary in Fe(1+d)Te(1-x)Se(x)
• Neutron scattering study of the oxypnictide superconductor La(O,F)FeAs

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