The Stoichiometry of FeSe

Abstract

Tetragonal iron selenide, FeSe, the layered parent compound of the recently discovered superconducting arsenide family, has previously been shown to be non magnetic and superconducting with a critical temperature near 8 K. There has, however, been a lack of consensus as to whether selenium vacancies present due to large deviations from ideal stoichiometry are required to give rise to the superconductivity. Here we describe the results of experiments that demonstrate simply that superconducting iron selenide can only be synthesized as a pure material when near stoichiometric (i.e. FeSe). Significant selenium deficiency or excess gives rise to secondary magnetic phases, and a suppression of the superconductivity.

References in corpus (7)

• Extreme Sensitivity of Superconductivity to Stoichiometry in FeSe (Fe1+dSe)
• Crystal structure of the new FeSe1-x superconductor
• Magnetism Driven by Anion Vacancies in Superconducting $\alpha$--FeSe${}_{1-x}$
• Growth and Superconductivity of FeSex Crystals
• Evidence for Unconventional Superconductivity in Arsenic-Free Iron-Based Superconductor FeSe : A ^77Se-NMR Study
• Neutron scattering Measurements of the phonon density of states of FeSe${}_{1-x}$ superconductors
• Electronic Structure of Superconducting FeSe Studied by High-Resolution Photoemission Spectroscopy

Cited by in corpus (26)

• Superconductivity in Iron Compounds
• The crystal structure of FeSe0.44Te0.56
• Temperature dependence of lower critical field Hc1(T) shows nodeless superconductivity in FeSe
• Role of point defects in spinel Mg chalcogenide conductors
• Superconductivity in the iron selenide KxFe2Se2 (0 <= x <= 1)
• New ternary ThCr2Si2-type iron-selenide superconducting materials: synthesis, properties and simulations
• Nodes in the Gap Function of LaFePO, the Gap Function of the Fe(Se,Te) Systems, and the STM Signature of the s${}_{\pm }$ Pairing
• A perspective on pnictide superconductors
• FeS: Structure and Composition Relations to Superconductivity and Magnetism
• Electronic Structure, Localization and Spin-State Transition in Cu-substituted FeSe: Fe${}_{1-x}$Cu${}_x$Se
• Nodal gaps in the nematic superconductor FeSe from heat capacity
• Effects of Disorder in FeSe : An Ab Initio Study
• The substitution effects on electronic structure of iron selenide superconductors
• Tuning stoichiometry and its impact on superconductivity of monolayer and multilayer FeSe on SrTiO3
• Mössbauer studies of powdered single crystals of FeTe0.5Se0.5
• Disorder effects in pnictides : a tunneling spectroscopy study
• MAGNETIC ANOMALY IN SUPERCONDUCTING FeSe
• Synthesis, phase stability, structural and physical properties of 11-type iron chalcogenides
• Synthesis, structural and physical properties of ${\delta }^{\prime }$-FeSe${}_{1-x}$
• Transition-Metal Substitutions in Iron Chalcogenides
• Double epitaxy of tetragonal and hexagonal phases in the FeSe system
• Stoichiometry and defect superstructures in epitaxial FeSe films on SrTiO3
• The Superconducting Transition Temperatures of Fe1+xSe1--y, Fe1+xSe1--yTey and (K/Rb/Cs)zFe2--xSe2
• The role of correlations in the high-pressure phase of FeSe
• Stoichiometric FeTe is a Superconductor
• Electronic Structure of $\text{Fe}{\text{Se}}_{1-x}{\text{Te}}_x$ Studied by X-ray Spectroscopy and Density Functional Theory