Distinct high-T transitions in underdoped Ba${}_{1-x}$K${}_x$Fe${}_2$As${}_2$

Abstract

In contrast to the simultaneous structural and magnetic first order phase transition $T_0$ previously reported, our detailed investigation on an underdoped Ba${}_{0.84}$K${}_{0.16}$Fe${}_2$As${}_2$ single crystal unambiguously revealed that the transitions are not concomitant. The tetragonal ($\tau$: I4/mmm) - orthorhombic ($\vartheta$: Fmmm) structural transition occurs at $T_S\simeq$ 110 K, followed by an adjacent antiferromagnetic (AFM) transition at $T_N\simeq$ 102 K. Hysteresis and coexistence of the $\tau$ and $\vartheta$ phases over a finite temperature range observed in our NMR experiments confirm the first order character of the structural transition and provide evidence that both $T_S$ and $T_N$ are strongly correlated. Our data also show that superconductivity (SC) develops in the $\vartheta$ phase below $T_c$ = 20 K and coexists with long range AFM. This new observation, $T_S\ne T_N$, firmly establishes another similarity between the hole-doped BaFe${}_2$As${}_2$ via K substitution and the electron-doped iron-arsenide superconductors.

4 pages, 3 figures

References in corpus (23)

• Superconductivity at 38 K in the iron arsenide (Ba1-xKx)Fe2As2
• Superconductivity at 43 K in Samarium-arsenide Oxides $SmFeAs{O}_{1-x}{F}_x$
• Spin density wave anomaly at 140 K in the ternary iron arsenide BaFe2As2
• Magnetic order in BaFe2As2, the parent compound of the FeAs based superconductors in a new structural family
• Effects of Co substitution on thermodynamic and transport properties and anisotropic $H_{c2}$ in Ba(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$ single crystals
• Determination of the phase diagram of the electron doped superconductor Ba(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$
• Anisotropic thermodynamic and transport properties of single crystalline (Ba${}_{1-x}$K${}_x$)Fe${}_2$As${}_2$ (x = 0 and 0.45)
• Superconductivity and Crystal Structures of (Ba1-xKx)Fe2As2 (x = 0 - 1)
• Coexistence of the spin-density-wave and superconductivity in the (Ba,K)Fe2As2
• Phase transitions in LaFeAsO: structural, magnetic, elastic, and transport properties, heat capacity and Mossbauer spectra
• Coexistence of static magnetism and superconductivity in SmFeAsO1-xFx as revealed by muon spin rotation
• Commensurate Itinerant Antiferromagnetism in BaFe2As2: 75As-NMR Studies on a Self-Flux Grown Single Crystal
• Electronic phase separation in the slightly underdoped iron pnictide superconductor Ba(1-x)K(x)Fe(2)As(2)
• A neutron scattering study of the interplay between structure and magnetism in Ba(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$
• Upper critical field, anisotropy, and superconducting properties of Ba${}_{1-x}$K${}_x$Fe${}_2$As${}_2$ single crystals
• Quasiparticle Heat Transport in Ba${}_{1-x}$K${}_x$Fe${}_2$As${}_2$: Evidence for a k-dependent Superconducting Gap without Nodes
• Homogeneous vs. inhomogeneous coexistence of magnetic order and superconductivity probed by NMR in Co and K doped iron pnictides
• 75As NMR Study of Hole-Doped Superconductor Ba1-xKxFe2As2 (Tc = 38K)
• Competition of magnetism and superconductivity in underdoped (Ba1-xKx)Fe2As2
• The role of striction at magnetic and structural transitions in iron-pnictides
• Microscopic study of the effect of impurities on the first order spin density wave transition in BaFe${}_2$As${}_2$
• 75As NMR study of the ternary iron arsenide BaFe2As2
• Magnetic and lattice coupling in single-crystal SrFe${}_2$As${}_2$: A neutron scattering study

Cited by in corpus (4)

• High-temperature superconductivity in iron-based materials
• Magnetoelastic Coupling in the Phase Diagram of Ba1-xKxFe2As2
• Direct observation of local K variation and its correlation to electronic inhomogeneity in (Ba1-xKx)Fe2As2 Pnictide
• Superconductivity and normal state properties of single-crystalline Tl0.47Rb0.34Fe1.63Se2 as seen via 77Se and 87Rb NMR