Effect of heavy-ion irradiation on London penetration depth in over-doped Ba(Fe,Co)2As2

Abstract

Irradiation with 1.4 GeV ${}^{208}$Pb ions was used to induce artificial disorder in single crystals of iron-arsenide superconductor Ba(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$ and to study its effect on the temperature-dependent London penetration depth and transport properties. Study was undertaken on overdoped single crystals with $x$=0.108 and $x$=0.127 characterized by notable modulation of the superconducting gap. Irradiation with doses 2.22$\times 10^{11}$$\text{d}$/cm${}^2$ and 2.4$\times 10^{11}$$\text{d}$/cm${}^2$, corresponding to the matching fields of $B_{\varphi }=$6 T and 6.5 T, respectively, suppresses the superconducting $T_c$ by approximately 0.3 to 1 K. The variation of the low-temperature penetration depth in both pristine and irradiated samples is well described by the power-law, $\Delta \lambda (T)=A{T}^n$. Irradiation increases the magnitude of the pre-factor $A$ and decreases the exponent $n$, similar to the effect of irradiation in optimally doped samples. This finding supports universal $s_{\pm }$ pairing in Ba(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$ compounds for the whole Co doping range.

References in corpus (10)

• High-temperature superconductivity in iron-based materials
• Is LaO${}_{1-x}$F${}_x$FeAs an electron-phonon superconductor ?
• 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
• Magnetic Penetration Depth in Unconventional Superconductors
• The BCS-like gap in superconductor SmFeAsO_0.85F_0.15
• Anisotropy of the Optimally-Doped Iron Pnictide Superconductor Ba(Fe0.926Co0.074)2As2
• Unconventional London penetration depth in Ba(Fe0.93Co0.07)2As2 single crystals
• The London penetration depth in single crystals of Ba(Fe_{1-x}Co_x)_2As_2 at various doping levels
• Orbital upper critical field of type-II superconductors with pair breaking
• Magneto-optical study of Ba(Fe${}_{1-x}$T${}_x$)${}_2$As${}_2$ (T=Co, Ni) single crystals irradiated with heavy-ions

Cited by in corpus (10)

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• Effect of electron irradiation on superconductivity in single crystals of Ba(Fe${}_{1-x}$Ru${}_x$)${}_2$As${}_2$ ($x=$0.24)
• A comprehensive scenario of the single crystal growth and doping dependence of resistivity and anisotropic upper critical fields in (Ba${}_{1-x}$K${}_x$)Fe${}_2$As${}_2$ ($0.22\le x\le 1$)
• Impurities in multiband superconductors
• Effects of electron irradiation on resistivity and London penetration depth of Ba${}_{1-x}$K${}_x$Fe${}_2$As${}_2$ ($x\le$ 0.34) iron - pnictide superconductor
• Using electron irradiation to probe iron - based superconductors
• Effects of heavy-ion irradiation on FeSe
• Comparative study of the effects of electron irradiation and natural disorder in single crystals of SrFe${}_2$(As${}_{1-x}$P${}_x$)${}_2$ ($x=$0.35) superconductor
• Impurity effect and suppression to superconductivity in Na(Fe${}_{0.97-x}$Co${}_{0.03}$T${}_x$)As (T=Cu, Mn)
• Ion-selective scattering studied by the variable-energy electron irradiation of Ba${}_{0.2}$K${}_{0.8}$Fe${}_2$As${}_2$ superconductor