The role of the nominal iron content in the structural, compositional and physical properties of BaFe${}_{2+\delta }$S${}_3$

Abstract

BaFe${}_2$S${}_3$ is a quasi-one-dimensional antiferromagnetic insulator that becomes superconducting under hydrostatic pressure. The magnetic ordering temperature, $T_N$, as well as the presence of superconductivity have been found to be sample dependent. It has been argued that the Fe content may play a decisive role, with the use of 5%mol excess Fe being reportedly required during the synthesis to optimize the magnetic ordering temperature and the superconducting properties. However, it is yet unclear whether an Fe off-stoichiometry is actually present in the samples, and how it affects the structural, magnetic and transport properties. Here, we present a systematic study of compositional, structural and physical properties of BaFe${}_{2+\delta }$S${}_3$ as a function of the nominal Fe excess $\delta$. As $\delta$ increases, we observe the presence of an increasing fraction of secondary phases but no systematic change in the composition or crystal structure of the main phase. Magnetic susceptibility curves are influenced by the presence of magnetic secondary phases. The previously reported maximum of $T_N$ at $\delta$=0.1 was not confirmed. Samples with nominal $\delta$=0 present the lowest $T_N$ and the resistivity anomaly at the highest temperature $T^{\ast }$ while, for $\delta \ge 0.05$, both quantities and the transport gap are seemingly $\delta$-independent. Finally, we show that crystals free of ferromagnetic spurious phases can be obtained by remelting samples with nominal $\delta$=0.05 in a Bridgman process.

arXiv comment11 pages, 8 figures

References in corpus (15)

• Surprises on the Way from 1D to 2D Quantum Magnets: the Novel Ladder Materials
• Pressure induced superconductivity in CaFe${}_2$As${}_2$
• Pressure-induced Superconductivity in the Iron-based Ladder Material BaFe2S3
• Superconductivity under high pressure in LaFeAsO
• Variable-range hopping in quasi-one-dimensional electron crystals
• Spin Glass and Semiconducting Behavior in 1D BaFe2-δSe3 Crystals
• Enhancement of the superconducting critical temperature in Bi${}_2$Sr${}_2$CaCu${}_2$O${}_{8+\delta }$ by controlling disorder outside CuO${}_2$ planes
• Pressure-driven phase transition from antiferromagnetic semiconductor to nonmagnetic metal in two-leg ladders $A$Fe${}_2$$X$${}_3$ ($A$=Ba or K, $X$=S or Se)
• Crystal Structure of BaFe2Se3 as a Function of Temperature and Pressure: Phase Transition Phenomena and High-Order Expansion of Landau Potential
• Gradual Enhancement of Stripe-Type Antiferromagnetism in Spin Ladder Material BaFe${}_2$S${}_3$ Under Pressure
• Bandwidth controlled insulator-metal transition in BaFe${}_2$S${}_3$: A Mössbauer study under pressure
• Strong electronic correlations and Fermi surface reconstruction in the quasi-one dimensional iron superconductor BaFe2S3
• Microscopic description of insulator-metal transition in high-pressure oxygen
• Non-superconducting electronic ground state in pressurized BaFe${}_2$S${}_3$ and BaFe${}_2$S${}_{2.5}$Se${}_{0.5}$
• Magnetic-order-driven metal-insulator transitions in the quasi-one-dimensional spin-ladder compounds BaFe${}_2$S${}_3$ and BaFe${}_2$Se${}_3$

Cited by in corpus (1)

• Pressure-induced superconductivity in iron-based spin-ladder compound BaFe2+δ(S1-Sex)3