Doping effect of Cu and Ni impurities on the Fe-based superconductor Ba0.6K0.4Fe2As2
arXiv:1304.4568 · doi:10.1209/0295-5075/104/37007
Abstract
Copper and Nickel impurities have been doped into the iron pnictide superconductor Ba0.6K0.4Fe2As2. Resistivity measurements reveal that Cu and Ni impurities suppress superconducting transition temperature T_c with rates of ΔT_c/Cu-1% = -3.5 K and ΔT_c/Ni-1% = -2.9 K respectively. Temperature dependence of Hall coefficient R_H of these two series of samples show that both Cu-doping and Ni-doping can introduce electrons into Ba0.6K0.4Fe2As2. With more doping, the sign of R_H gradually changes from positive to negative, while the changing rate of Cu-doped samples is much faster than that of Ni-doped ones. Combining with the results of first-principles calculations published previously and the non-monotonic evolution of the Hall coefficient in the low temperature region, we argue that when more Cu impurities were introduced into Ba0.6K0.4Fe2As2, the removal of Fermi spectral weight in the hole-like Fermi surfaces is much stronger than that in the electron-like Fermi surfaces, which is equivalent to significant electron doping effect. DC magnetization and the lattice constants analysis reveal that static magnetic moments and notable lattice compression have been formed in Cu-doped samples. It seems that the superconductivity can be suppressed by the impurities disregard whether they are magnetic or nonmagnetic in nature. This gives strong support to a pairing gap with a sign reversal, like S^\pm. However, the relatively slow suppression rates of T_c show the robustness of superconductivity of Ba0.6K0.4Fe2As2 against impurities, implying that multi-pairing channels may exist in the system.
7 pages, 7 figures
References in corpus (15)
- Superconductivity at 38 K in the iron arsenide (Ba1-xKx)Fe2As2
- Unconventional pairing originating from disconnected Fermi surfaces in superconducting LaFeAsOF}
- Funtional Renormalization Group Study of the Pairing Symmetry and Pairing Mechanism of the FeAs Based High Temperature Superconductors
- As NMR studies of superconducting LaOFFeAs
- Microwave Penetration Depth and Quasiparticle Conductivity in PrFeAsO_1-y Single Crystals : Evidence for a Full-Gap Superconductor
- Evidence for nodal superconductivity in LaFePO
- NMR relaxation rate in superconducting pnictides: extended scenario
- Where Are the Extra d Electrons in Transition-Metal Substituted Fe Pnictides?
- Superfluid density of the s-wave state for the iron-based superconductors
- Quasiparticle Heat Transport in BaKFeAs: Evidence for a k-dependent Superconducting Gap without Nodes
- Metal - Insulator transition in Fe1.01-xCuxSe
- Close relationship between superconductivity and the bosonic mode in Ba0.6K0.4Fe2As2 and Na(Fe0.975Co0.025)As
- Large decrease in the critical temperature of superconducting LaFeAsO0.85 compounds doped with 3% atomic weight of nonmagnetic Zn impurities
- Single Impurity Problem in Iron-Pnictide Superconductors
- Universal pair-breaking in transition metal-substituted iron-pnictide superconductors
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