Effect of inelastic scattering on the nuclear magnetic relaxation rate 1/T1T in iron-based superconductors
arXiv:1206.1399 · doi:10.1088/0953-2048/25/8/084006
Abstract
We present a microscopic study of the nuclear magnetic relaxation rate 1/T1 based on the five-orbital model for iron-based superconductors. We mainly discuss the effect of the "inelastic" quasi-particle damping rate γ due to many-body interaction on the size of the coherence peak, for both s++ and s+- wave superconducting states. We focus on Ba(Fe1-xCox)2As2, and systematically evaluate γ in the normal state from the experimental resistivity, from optimally to over-doped compounds. Next, γ in the superconducting state is calculated microscopically based on the second order perturbation theory. In optimally doped compounds (Tc ~ 30 K), it is revealed that the coherence peak on 1/T1T is completely suppressed due to large γ for both s++ and s+- wave states. On the other hand, in heavily over doped compounds with Tc < 10 K, the coherence peak could appear for both pairing states, since γ at Tc is quickly suppressed in proportion to Tc^2. By making careful comparison between theoretical and experimental results, we conclude that it is difficult to discriminate between s++ and s+- wave states from the present experimental results.
9 pages, 6 figures, invited submission to Superconductor Science and Technology focus issue on iron-based superconductors
References in corpus (23)
- Unconventional pairing originating from disconnected Fermi surfaces in superconducting LaFeAsOF}
- Observation of Fermi-surface-dependent nodeless superconducting gaps in Ba0.6K0.4Fe2As2
- Magnetism, superconductivity, and pairing symmetry in Fe-based superconductors
- Multiband magnetism and superconductivity in Fe-based compounds
- Evolution from Itinerant Antiferromagnet to Unconventional Superconductor with Fluorine Doping in La(O_{1-x}F_{x})FeAs Revealed by ^{75}As and ^{139}La Nuclear Magnetic Resonance
- As NMR studies of superconducting LaOFFeAs
- Microwave Penetration Depth and Quasiparticle Conductivity in PrFeAsO_1-y Single Crystals : Evidence for a Full-Gap Superconductor
- Hall effect and resistivity study of the magnetic transition, carrier content and Fermi liquid behavior in Ba(Fe(1-x) Cox)2As2
- Electron Correlations in the Low Carrier Density LaFeAsO0.89F0.11 Superconductor (Tc = 28 K)
- NMR relaxation rate in superconducting pnictides: extended scenario
- Spin susceptibility, phase diagram, and quantum criticality in the electron-doped high Tc Superconductor Ba[Fe(1-x)Co(x)]2As2
- Anomalous Transport Phenomena in Fermi Liquids with Strong Magnetic Fluctuations
- Quantum oscillations in the parent magnetic phase of an iron arsenide high temperature superconductor
- Orbital Fluctuation Theory in Iron Pnictides: Effects of As-Fe-As Bond Angle, Isotope Substitution, and -Orbital Pocket on the Superconductivity
- Possible pairing states of the Fe-based superconductors
- Strong-coupling Spin-singlet Superconductivity with Multiple Full Gaps in Hole-doped BaKFeAs Probed by Fe-NMR
- On the Superconductivity of LaFe1-yCoyAsO1-xFx
- As NQR and NMR studies of superconductivity and electron correlations in iron arsenide LiFeAs
- Two superconducting gaps in LaFeAsO0.92F0.08 revealed by 75As nuclear quadrupole resonance
- Fermi surface of SrFeP determined by de Haas-van Alphen effect
- Possible two-gap superconductivity in NdFeAs(O,F) probed by point-contact Andreev-reflection spectroscopy
- Impurity-induced in-gap state and Tc in sign-reversing s-wave superconductors: analysis of iron oxypnictide superconductors
- Non-Fermi-Liquid Transport Phenomena and Superconductivity Driven by Orbital Fluctuations in Iron Pnictides: Analysis by Fluctuation-Exchange Approximation