Orbital selectivity of layer resolved tunneling on iron superconductor Ba0.6K0.4Fe2As2

Abstract

We use scanning tunneling microscopy/spectroscopy (STM/S) to elucidate the Cooper pairing of the iron pnictide superconductor Ba0.6K0.4Fe2As2. By a cold-cleaving technique, we obtain atomically resolved termination surfaces with different layer identities. Remarkably, we observe that the low-energy tunneling spectrum related to superconductivity has an unprecedented dependence on the layer-identity. By cross-referencing with the angle-revolved photoemission results and the tunneling data of LiFeAs, we find that tunneling on each termination surface probes superconductivity through selecting distinct Fe-3d orbitals. These findings imply the real-space orbital features of the Cooper pairing in the iron pnictide superconductors, and propose a new and general concept that, for complex multi-orbital material, tunneling on different terminating layers can feature orbital selectivity.

References in corpus (34)

• Unconventional pairing originating from disconnected Fermi surfaces in superconducting LaFeAsO${}_{1-x}$F${}_x$}
• High-temperature superconductivity in iron-based materials
• LaFeAsO${}_{1-x}$F${}_x$: A low carrier density superconductor near itinerant magnetism
• Near-degeneracy of several pairing channels in multiorbital models for the Fe-pnictides
• Negative flat band magnetism in a spin-orbit coupled correlated kagome magnet
• Discovery of Orbital-Selective Cooper Pairing in FeSe
• Giant and anisotropic many-body spin-orbit tunability in a strongly correlated kagome magnet
• Observation of a Robust Zero-energy Bound State in Iron-based Superconductor Fe(Te,Se)
• Visualizing heavy fermions emerging in a quantum critical Kondo lattice
• Observation of universal strong orbital-dependent correlation effects in iron chalcogenides
• Spectroscopic scanning tunneling microscopy insights into Fe-based superconductors
• Role of the orbital degree of freedom in iron-based superconductors
• Anisotropic Energy Gaps of Iron-based Superconductivity from Intra-band Quasiparticle Interference in LiFeAs
• Unconventional Anisotropic s-Wave Superconducting Gaps of LiFeAs Iron-Pnictide Superconductor
• Scanning Tunneling Microscopy/Spectroscopy of Vortices in LiFeAs
• Observation of Lattice and Andreev Bound States of Vortices in Ba0.6K0.4Fe2As2 Single Crystals with Scanning Tunneling Microscopy/Spectroscopy
• Anisotropic spin fluctuations in detwinned FeSe
• Scanning tunneling spectroscopy of superconducting LiFeAs single crystals: Evidence for two nodeless energy gaps and coupling to a bosonic mode
• Extraordinary quasiparticle scattering and bandwidth-control by dopants in iron-based superconductors
• Orbital Characters Determined from Fermi Surface Intensity Patterns using Angle-Resolved Photoemission Spectroscopy
• Evidence of a spin resonance mode in the iron-based superconductor Ba${}_{0.6}$K${}_{0.4}$Fe${}_2$As${}_2$ from scanning tunneling spectroscopy
• Strong pairing at iron $3d_{xz,yz}$ orbitals in hole-doped BaFe${}_2$As${}_2$
• Pairing Mechanism in Hunds Metal Superconductors and the Universality of the Superconducting Gap to Critical Temperature Ratio
• Orbital selective spin excitations and their impact on superconductivity of LiFe1-xCoxAs
• Mapping the Electronic Structure of Each Ingredient Oxide Layer of High-$T_{\text{c}}$ Cuprate Superconductor Bi2Sr2CaCu2O8+δ
• Field-free platform for topological zero-energy mode in superconductors LiFeAs and PbTaSe${}_2$
• Surface terminations and layer-resolved spectroscopy in 122 iron pnictide superconductors
• Extended Hubbard model of superconductivity driven by charge fluctuations in iron-pnictides
• Quantum phase transition of correlated iron-based superconductivity in LiFe${}_{1-x}$Co${}_x$As
• Towards a quantitative description of tunneling conductance of superconductors: application to LiFeAs
• Vector field controlled vortex lattice symmetry in LiFeAs
• Tracing the electronic pairing glue in unconventional superconductors via inelastic Scanning Tunneling Spectroscopy
• Spin fluctuation anisotropy as a probe of orbital-selective hole-electron quasiparticle excitations in detwinned Ba(Fe1-xCox)2As2
• Spectroscopic evidence of nematic fluctuations in LiFeAs

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