Local inhomogeneity and filamentary superconductivity in Pr-doped CaFe${}_2$As${}_2$

Abstract

We use multi-scale techniques to determine the extent of local inhomogeneity and superconductivity in Ca${}_{0.86}$Pr${}_{0.14}$Fe${}_2$As${}_2$ single crystal. The inhomogeneity is manifested as a spatial variation of praseodymium concentration, local density of states, and superconducting order parameter. We show that the high-$T_c$ superconductivity emerges from clover-like defects associated with Pr dopants. The highest $T_c$ is observed in both the tetragonal and collapsed tetragonal phases, and its filamentary nature is a consequence of non-uniform Pr distribution that develops localized, isolated superconducting regions within the crystals.

Accepted for publication in Phys. Rev. Lett. (January 6, 2014)

References in corpus (15)

• Superconductivity at 38 K in the iron arsenide (Ba1-xKx)Fe2As2
• Superconductivity at 43 K in Samarium-arsenide Oxides $SmFeAs{O}_{1-x}{F}_x$
• Superconductivity at 22 K in Co-doped BaFe2As2 Crystals
• Visualizing pair formation on the atomic scale in the high-Tc superconductor Bi2Sr2CaCu2O8+d
• The Unprecedented Giant Coupling of Fe-spin State and the As-As Hybridization in Iron-Pnictide
• Scanning Tunneling Spectroscopy and Vortex Imaging in the Iron-Pnictide Superconductor BaFe${}_{1.8}$Co${}_{0.2}$As${}_2$
• Superconductivity in SrFe_(2-x)Co_xAs_2: Internal Doping of the Iron Arsenide Layers
• Imaging nanoscale Fermi surface variations in an inhomogeneous superconductor
• The cleavage surface of the BaFe_(2-x)Co_(x)As_(2) and Fe_(y)Se_(1-x)Te_(x) superconductors: from diversity to simplicity
• Nanoscale superconducting gap variations, strong coupling signatures and lack of phase separation in optimally doped BaFe1.86Co0.14As2
• Measurement of a Sign-Changing Two-Gap Superconducting Phase in Electron-Doped Ba(Fe_{1-x}Co_x)_2As_2 Single Crystals using Scanning Tunneling Spectroscopy
• Effect of annealing on the specific heat of Ba(Fe1-xCox)2As2
• Pseudogap-less high T${}_c$ superconductivity in BaCo${}_x$Fe${}_{2-x}$As${}_2$
• Quenched Fe Moment in the Collapsed Tetragonal Phase of Ca${}_{1-x}$Pr${}_x$Fe${}_2$As${}_2$
• Experimental investigation of the electronic structure of Ca${}_{0.83}$La${}_{0.17}$Fe${}_2$As${}_2$

Cited by in corpus (24)

• Anisotropic Superconductivity of Ca1-xLaxFeAs2 (x ~ 0.18) Single Crystal
• Evidence for Defect-induced Superconductivity up to 49 K in (Ca1-xRx)Fe2As2
• Deep data mining in a real space: Separation of intertwined electronic responses in a lightly-doped BaFe2As2
• Tetragonal and collapsed-tetragonal phases of CaFe2As2 -- a view from angle-resolved photoemission and dynamical mean field theory
• Gossamer bulk high-temperature superconductivity in FeSe
• Improving quantum-transition temperatures in BaFe2As2-based crystals by removing local-lattice strain & electronic-structure disorder
• A linear-scaling algorithm for rapid computation of inelastic transitions in the presence of multiple electron scattering
• Conductivity of anisotropic inhomogeneous superconductors above critical temperature
• Charge-Density Waves vs. Superconductivity: Some Results and Future Perspectives
• Sign change in c-axis thermal expansion and lattice collapse by Ni substitution in Co1-xNixZr2 superconductors
• The collapsed tetragonal phase as a strongly covalent and fully nonmagnetic state: persistent magnetism with interlayer As-As bond formation in Rh-doped Ca${}_{0.8}$Sr${}_{0.2}$Fe${}_2$As${}_2$
• Formation of As-As Bond and Its Effect on Absence of Superconductivity in Collapsed Tetragonal Phase of Ca0.86Pr0.14Fe2As2 : An Optical Spectroscopy Study
• Anisotropic zero-resistance onset in organic superconductors
• Superconductivity and a van Hove singularity confined to the surface of a topological semimetal
• Origin of efficient thermoelectric performance in half-Heusler FeNb${}_{0.8}$Ti${}_{0.2}$Sb
• Effects of post-annealing and cobalt co-doping on superconducting properties of (Ca,Pr)Fe2As2 single crystals
• Role of electron-electron interactions in the charge dynamics of rare-earth-doped CaFe2As2
• Reversible Tuning of the Collapsed Tetragonal Phase Transition in CaFe2As2 by Separate Control of Chemical Pressure and Electron Doping
• Drastic electronic structure reconstruction of Ca${}_{1-x}$Pr${}_x$Fe${}_2$As${}_2$ in the collapsed tetragonal phase
• Phase Diagram and Weak-link Behavior in Nd-doped CaFe_2As_2
• Inhomogeneous superconductivity onset in FeSe studied by transport properties
• Superconductivity with Tc=7 K under pressure for Cu-, and Au-doped BaFe2As2
• Nanoscale Interlayer Defects in Iron Arsenides
• Superfluid response of two-dimensional filamentary superconductors