Towards a quantitative description of tunneling conductance of superconductors: application to LiFeAs

Abstract

Since the discovery of iron-based superconductors, a number of theories have been put forward to explain the qualitative origin of pairing, but there have been few attempts to make quantitative, material-specific comparisons to experimental results. The spin-fluctuation theory of electronic pairing, based on first-principles electronic structure calculations, makes predictions for the superconducting gap. Within the same framework, the surface wave functions may also be calculated, allowing, e.g., for detailed comparisons between theoretical results and measured scanning tunneling topographs and spectra. Here we present such a comparison between theory and experiment on the Fe-based superconductor LiFeAs. Results for the homogeneous surface as well as impurity states are presented as a benchmark test of the theory. For the homogeneous system, we argue that the maxima of topographic image intensity may be located at positions above either the As or Li atoms, depending on tip height and the setpoint current of the measurement. We further report the experimental observation of transitions between As and Li-registered lattices as functions of both tip height and setpoint bias, in agreement with this prediction. Next, we give a detailed comparison between the simulated scanning tunneling microscopy images of transition-metal defects with experiment. Finally, we discuss possible extensions of the current framework to obtain a theory with true predictive power for scanning tunneling microscopy in Fe-based systems.

arXiv comment14 pages, 15 figures, published version

References in corpus (39)

• Unconventional pairing originating from disconnected Fermi surfaces in superconducting LaFeAsO${}_{1-x}$F${}_x$}
• LiFeAs: An Intrinsic FeAs-based Superconductor with Tc = 18K
• Full orbital calculation scheme for materials with strongly correlated electrons
• Spin-triplet p-wave pairing in a 3-orbital model for iron pnictide superconductors
• Tight-binding models for the new iron based superconductor materials
• Anisotropic Energy Gaps of Iron-based Superconductivity from Intra-band Quasiparticle Interference in LiFeAs
• Using Gap Symmetry and Structure to Reveal the Pairing Mechanism in Fe-based Superconductors
• Spin dynamics and an orbital-antiphase pairing symmetry in iron-based superconductors
• Unconventional Anisotropic s-Wave Superconducting Gaps of LiFeAs Iron-Pnictide Superconductor
• Space group symmetry, spin-orbit coupling and the low energy effective Hamiltonian for iron based superconductors
• Insulating Ferromagnetism in La${}_4$Ba${}_2$Cu${}_2$O${}_{10}$: an \textit{Ab Initio} Wannier Function Analysis
• Sensitivity of the superconducting state and magnetic susceptibility to key aspects of electronic structure in ferropnictides
• On the multi-orbital band structure and itinerant magnetism of iron-based superconductors
• Do Transition Metal Substitutions Dope Carriers in Iron Based Superconductors?
• One-sign order parameter in iron based superconductor
• Effects of correlation in LiFeAs
• Interpretation of scanning tunneling quasiparticle interference and impurity states in cuprates
• First-principles calculation of transition-metal impurities in LaFeAsO
• Scanning tunneling spectroscopy of superconducting LiFeAs single crystals: Evidence for two nodeless energy gaps and coupling to a bosonic mode
• Orbital selective Fermi surface shifts and mechanism of high T${}_c$ superconductivity in correlated AFeAs (A=Li,Na)
• Superconductivity from repulsion in LiFeAs: novel s-wave symmetry and potential time-reversal symmetry breaking
• Pairing symmetry of the one-band Hubbard model in the paramagnetic weak-coupling limit: a numerical RPA study
• Superconducting gap in LiFeAs from three-dimensional spin-fluctuation pairing calculations
• Visualization of atomic-scale phenomena in superconductors: application to FeSe
• Mn local moments prevent superconductivity in iron-pnictides Ba(Fe 1-x Mn x)2As2
• Unconventional disorder effects in correlated superconductors
• Enhancing magnetic stripe order in iron pnictides by RKKY exchange interactions
• Impurity states and cooperative magnetic order in Fe-based superconductors
• Spectral properties of transition metal pnictides and chalcogenides: angle-resolved photoemission spectroscopy and dynamical mean field theory
• Friedel Oscillations as a Probe of Fermionic Quasiparticles
• Can disorder alone destroy the eg' hole pockets of NaxCoO2? A Wannier function based first-principles method for disordered systems
• Impurity-Induced Electronic Nematic State in Iron-Pnictide Superconductors
• Gap Symmetry and Stability Analysis in the Multi-Orbital Fe-Based Superconductors
• Spectral decomposition and matrix element effects in scanning tunneling spectroscopy of Bi${}_2$Sr${}_2$CaCu${}_2$O${}_{8+\delta }$
• Impact of Iron-site defects on Superconductivity in LiFeAs
• Possible unconventional superconductivity in substituted BaFe${}_2$As${}_2$ revealed by magnetic pair-breaking studies
• Improper s-wave symmetry for the electronic pairing in iron-based superconductors by first-principles calculation
• Electronic vortex structure of Fe-based superconductors: application to LiFeAs
• NMR study of electronic correlations in Mn-doped Ba(Fe1-xCox)2As2 and BaFe(As1-xPx)2

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