Peculiar Phase Diagram with Isolated Superconducting Regions in ThFeAsN${}_{1-x}$O${}_x$

Abstract

ThFeAsN${}_{1-x}$O${}_x$ ($0\le x\le 0.6$) system with heavy electron doping has been studied by the measurements of X-ray diffraction, electrical resistivity, magnetic susceptibility and specific heat. The non-doped compound exhibits superconductivity at $T_{\mathrm{c}}^{\mathrm{onset}}=30$ K, which is possibly due to an internal uniaxial chemical pressure that is manifested by the extremely small value of As height with respect to the Fe plane. With the oxygen substitution, the $T_{\mathrm{c}}$ value decreases rapidly to below 2 K for $0.1\le x\le 0.2$, and surprisingly, superconductivity re-appears in the range of $0.25\le x\le 0.5$ with a maximum $T_{\mathrm{c}}^{\mathrm{onset}}$ of 17.5 K at $x=0.3$. For the normal-state resistivity, while the samples in intermediate non-superconducting interval exhibit Fermi liquid behavior, those in other regions show a non-Fermi-liquid behavior. The specific heat jump for the superconducting sample of $x=0.4$ is $\Delta C/(\gamma T_{\mathrm{c}})=0.89$, which is discussed in terms of anisotropic superconducting gap. The peculiar phase diagram in ThFeAsN${}_{1-x}$O${}_x$ presents additional ingredients for understanding the superconducting mechanism in iron-based superconductors.

arXiv comment10 pages, 7 figures

References in corpus (28)

• Superconductivity at 38 K in the iron arsenide (Ba1-xKx)Fe2As2
• Unconventional sign-reversing superconductivity in LaFeAsO_(1-x)F_x
• Superconductivity at 43 K in Samarium-arsenide Oxides $SmFeAs{O}_{1-x}{F}_x$
• The Puzzle of High Temperature Superconductivity in Layered Iron Pnictides and Chalcogenides
• Unconventional pairing originating from disconnected Fermi surfaces in superconducting LaFeAsO${}_{1-x}$F${}_x$}
• Thorium-doping induced superconductivity up to 56 K in Gd1-xThxFeAsO
• Superconductivity at 25 K in hole doped $(L{a}_{1-x}S{r}_x)OFeAs$
• Superconductivity in Co-doped LaFeAsO
• Contrasting Spin Dynamics Between Underdoped and Overdoped Ba(Fe[1-x]Co[x])2As2
• Two-dome structure in electron-doped iron arsenide superconductors
• Spin fluctuations and superconductivity in a 3D tight-binding model for BaFe2As2
• Weak-link behavior of grain boundaries in superconducting Ba(Fe1-xCox)2As2 bicrystals
• Elaboration of the alpha-Model Derived from the BCS Theory of Superconductivity
• Bipartite magnetic parent phases in the iron-oxypnictide superconductor
• Superconductivity in LaFeAs${}_{1-x}$P${}_x$O: effect of chemical pressures and bond covalency
• A New ZrCuSiAs-Type Superconductor: ThFeAsN
• Antiferromagnetic Spin Fluctuation above the Superconducting Dome and the Full-Gaps Superconducting State in LaFeAsO1-xFx Revealed by 75As-Nuclear Quadrupole Resonance
• Nodeless energy gaps of single-crystalline Ba0.68K0.32Fe2As2 as seen via 75As NMR
• Detection of antiferromagnetic ordering in heavily doped LaFeAsO1-xHx pnictide superconductors using nuclear-magnetic-resonance techniques
• Emergence of Novel Antiferromagnetic Order Intervening between Two Superconducting Phases in LaFe(As_1-x_P_x_)O: 31P-NMR Studies
• Multigap superconductivity in ThAsFeN investigated using muSR measurements
• Relationship between Superconductivity and Antiferromagnetism in LaFe(As${}_{1-x}$P${}_x$)O Revealed by ${}^{31}$P-NMR
• High-$T_{\mathrm{c}}$ superconductivity in undoped ThFeAsN
• Controlling Factors of Tc-Dome Structure in 1111-Type Iron Arsenide Superconductors
• Effect of nonmagnetic and magnetic impurities on the specific heat jump in anisotropic superconductors
• Heavy Electron doping-induced antiferromagnetic phase as the parent for iron-oxypnictide superconductor LaFeAsO1-xHx
• ThFeAsN in Relation to Other Iron-Based Superconductors
• Neutron powder diffraction study on the iron-based nitride superconductor ThFeAsN

Cited by in corpus (7)

• A brief review on muSR studies of unconventional Fe and Cr-based superconductors
• Superconductivity in Uncollapsed Tetragonal LaFe2As2
• BaTh${}_2$Fe${}_4$As${}_4$(N${}_{0.7}$O${}_{0.3}$)${}_2$: An Iron-Based Superconductor Stabilized by Inter-Block-Layer Charge Transfer
• Exploring multichannel superconductivity in ThFeAsN
• Absence of superconductivity in electron-doped chromium pnictides ThCrAsN${}_{1-x}$O${}_x$
• Universal quasi-degenerate orbital origin of two-dome phases in iron pnictide superconductors
• Neutron powder diffraction study on the non-superconducting phases of ThFeAsN${}_{1-x}$O${}_x$ ($x=0.15,0.6$) iron pnictide