First-order magnetic and structural phase transitions in Fe${}_{1+y}$Se${}_x$Te${}_{1-x}$

Abstract

We use bulk magnetic susceptibility, electronic specific heat, and neutron scattering to study structural and magnetic phase transitions in Fe${}_{1+y}$Se% ${}_x$Te${}_{1-x}$. Fe${}_{1.068}$Te exhibits a first order phase transition near 67 K with a tetragonal to monoclinic structural transition and simultaneously develops a collinear antiferromagnetic (AF) order responsible for the entropy change across the transition. Systematic studies of FeSeTe${}_x$ system reveal that the AF structure and lattice distortion in these materials are different from those of FeAs-based pnictides. These results call into question the conclusions of present density functional calculations, where FeSe${}_{1-x}$Te${}_x$ and FeAs-based pnictides are expected to have similar Fermi surfaces and therefore the same spin-density-wave AF order.

5 pages, 3 figures

References in corpus (22)

• Superconductivity at 38 K in the iron arsenide (Ba1-xKx)Fe2As2
• Magnetic Order versus superconductivity in the Iron-based layered La(O1-xFx)FeAs systems
• Superconductivity at 43 K in Samarium-arsenide Oxides $SmFeAs{O}_{1-x}{F}_x$
• Superconductivity at 41 K and its competition with spin-density-wave instability in layered CeO${}_{1-x}$F${}_x$FeAs
• Magnetic order in BaFe2As2, the parent compound of the FeAs based superconductors in a new structural family
• Density functional study of FeS, FeSe and FeTe: Electronic structure, magnetism, phonons and superconductivity
• Structural and magnetic phase diagram of CeFeAsO1-xFx and its relationship to high-temperature superconductivity
• Superconductivity at 27 K in tetragonal FeSe under high pressure
• Superconductivity and Phase Diagram in the Iron-based Arsenic-oxides ReFeAsO1-delta (Re = rare earth metal) without F-Doping
• Competing Orders and Spin-Density-Wave Instability in La(O${}_{1-x}$F${}_x$)FeAs
• Theory of Electron Nematic Order in LaOFeAs
• Superconductivity close to magnetic instability in Fe(Se1-xTex)0.82
• Tellurium substitution effect on superconductivity of the alpha-phase Iron Selenide
• Superconductivity at 25 K in hole doped $(L{a}_{1-x}S{r}_x)OFeAs$
• Lattice and magnetic instabilities in CaFe2As2: A single crystal neutron diffraction study
• Crystal structure of the new FeSe1-x superconductor
• Electron-Hole Symmetry and Magnetic Coupling in Antiferromagnetic LaOFeAs
• Antiferromagnetic superexchange interactions in LaOFeAs
• Spin and Lattice Structure of Single Crystal SrFe2As2
• Lattice and Magnetic structures of PrFeAsO, PrFeAsO0.85F0.15 and PrFeAsO0.85
• Magnetic Order of the Iron Spins in NdOFeAs
• Magnetic Ordering and Negative Thermal Expansion in PrFeAsO

Cited by in corpus (8)

• Bulk Superconductivity at 14 K in Single Crystals of Fe1+yTexSe1-x
• Fermi surface topology and low-lying quasiparticle dynamics of parent Fe${}_{1+x}$Te/Se Superconductor by orbital-polarization resolved ARPES
• Doping Driven ($\pi ,0$) Nesting and Magnetic Properties of Fe${}_{1+x}$Te Superconductors
• Short-range incommensurate magnetic order near the superconducting phase boundary in Fe(1+d)Te(1-x)Se(x)
• Successive phase transitions under high pressure in FeTe0.92
• Density Functional Study of the Over-Doped Iron Chalcogenide: TlFe${}_2$Se${}_2$ with ThCr${}_2$Si${}_2$ structure
• Neutron scattering patterns show Superconductivity in FeTe0.5Se0.5 likely results from itinerant electron fluctuations
• Superconductivity and Antiferromagnetism In Fe(Te1-xSx)y System