Definitive experimental evidence for two-band superconductivity in MgB2

Abstract

The superconducting gap of MgB2 has been studied by high-resolution angle-resolved photoemission spectroscopy (ARPES). The momentum(k)-resolving capability of ARPES enables us to identify the s- and p-orbital derived bands predicted from band structure calculations and to successfully measure the superconducting gap on each band. The results show that superconducting gaps with values of 5.5 meV and 2.2 meV open on the s-band and the p-band, respectively, but both the gaps close at the bulk transition temperature, providing a definitive experimental evidence for the two-band superconductivity in MgB2. The experiments validate the role of k-dependent electron-phonon coupling as the origin of multiple-gap superconductivity in MgB2.

PDF file only

References in corpus (23)

• Superconductivity of metallic boron in MgB_2
• Beyond Eliashberg superconductivity in MgB2: anharmonicity, two-phonon scattering, and multiple gaps
• Boron Isotope Effect in Superconducting MgB${}_2$
• Superconductivity of MgB2: Covalent Bonds Driven Metallic
• Electron-phonon interaction in the normal and superconducting states of MgB2
• Giant anharmonicity and non-linear electron-phonon coupling in MgB${}_2$; A combined first-principles calculations and neutron scattering study
• First-Principles Calculation of the Superconducting Transition in MgB2 within the Anisotropic Eliashberg Formalism
• Superconducting Properties of MgB2 Bulk Materials Prepared by High Pressure Sintering
• Two-Band Superconductivity in MgB2
• The reduced total isotope effect and its implications on the nature of superconductivity in MgB2
• ARPES Study of the Superconducting Gap Anisotropy in Bi_2Sr_2CaCu_2O_8+x
• Vortex Imaging in the pi-Band of Magnesium Diboride
• Heat Conduction in the Vortex State of NbSe_2: Evidence for Multi-Band Superconductivity
• Prediction of High Tc Superconductivity in Hole-doped LiBC
• Direct evidence for a multiple superconducting gap in MgB2 from high-resolution photoemission spectroscopy
• Evidence for Two-Band Superconductivity from Break Junction Tunneling on MgB2
• Electronic structure of MgB${}_2$ from angle-resolved photoemission spectroscopy
• Superconducting gap in the presence of bilayer splitting in underdoped Bi(Pb)2212
• Strong Coupling and Double Gap Density of States in Superconducting MgB2
• Energy bandstructures of MgB2 and the related compounds
• Two-Band-Type Superconducting Instability in MgB2
• Superconductivity Driven by the Interband Coulomb Interaction and Implications for the Superconducting Mechanism of MgB2
• Anisotropic s-wave superconductivity: comparison with experiments on MgB2 single crystals

Cited by in corpus (46)

• The Puzzle of High Temperature Superconductivity in Layered Iron Pnictides and Chalcogenides
• Electronic structure of quantum materials studied by angle-resolved photoemission spectroscopy
• Carbon-substitution effect on the electronic properties of MgB${}_2$ single crystals
• High Pressure and Road to Room Temperature Superconductivity
• A review of two-band superconductivity: materials and effects on the thermodynamic and reversible mixed-state properties
• Crossover from weak to strong pairing in unconventional superconductors
• Specific heat evidence for two-gap superconductivity in ternary-iron silicide Lu${}_2$Fe${}_3$Si${}_5$
• Sc substitution for Mg in MgB2: effects on Tc and Kohn anomaly
• Optical spectroscopy of superconducting Ba{0.55}K{0.45}Fe2As2: evidence for strong coupling to low energy bosons
• Enhancement of the irreversibility field by carbon substitution in single crystal MgB${}_2$
• Carbon-substitution dependent multiple superconducting gap of MgB${}_2$: a "sub-meV" resolution photoemission study
• Low-Temperature and High-Energy-Resolution Laser Photoemission Spectroscopy
• Field dependence of the vortex core size in a multi-band superconductor
• Electron-phonon effects on the Raman spectrum in MgB${}_2$
• Frustrated multiband superconductivity
• Point-contact spectroscopy of Al- and C-doped MgB2. Superconducting energy gaps and scattering studies
• BCS-BEC crossover of collective excitations in two-band superfluids
• Two-band superfluidity from the BCS to the BEC limit
• Study of temperature dependent atomic correlations in MgB${}_2$
• Observation of a Dirac nodal line in AlB2
• Proximity and Josephson effects in microstructures based on multiband superconductors
• Observation of Topological Surface State in High Temperature Superconductor MgB2
• Low-Energy Charge-Density Excitations in MgB${}_2$: Striking Interplay between Single-Particle and Collective Behavior for Large Momenta
• Superconducting electronic state in optimally doped YBa2Cu3O7-d observed with laser-excited angle-resolved photoemission spectroscopy
• Two-band superfluidity and intrinsic Josephson effect in alkaline-earth Fermi gases across an orbital Feshbach resonance
• Penetration depth, multiband superconductivity, and absence of muon-induced perturbation in superconducting PrOs${}_4$Sb${}_{12}$
• Strong interaction between electrons and collective excitations in multiband superconductor MgB2
• Stable Sarma State in Two-band Fermi Systems
• Infrared properties of Mg${}_{1-x}$Al${}_x($B${}_{1-y}$C${}_y$)${}_2$ single crystals in the normal and superconducting state
• Critical temperature of MgB${}_2$ ultrathin superconducting films: BCS model calculations in tight-binding approximation
• Damping of the de Haas-van Alphen oscillations in the superconducting state of MgB_2
• Coherence lengths for superconductivity in the two-orbital negative-U Hubbard model
• Characterization of high-quality MgB2(0001) epitaxial films on Mg(0001)
• Flux flow resistivity in the two-gap superconductivity
• Magnetic irreversibility and pinning force density in the Mo${}_{100-x}$Re${}_x$ alloy superconductors
• Superconducting Properties of Combustion Synthesized MgB2
• Isotope Effect on Electron-Phonon Interaction in Multiband Superconductor MgB2
• Band filling effects on coherence lengths and penetration depth in the two-orbital negative-U Hubbard model of superconductivity
• Asymmetric Fermion Superfluid with Inter- and Intra-Species Pairings
• Observation of pseudogap in MgB2
• Asymmetric Fermi Superfluid With Two Types Of Pairings
• Nonvolatile Magneto-Thermal Switching in MgB2
• Conduction electron spin-lattice relaxation time in the MgB2 superconductor
• Is Delta_{pi}-gap-only superconductivity possible in Mg_{1-x}Al_{x}B_{2} and Mg(B_{1-y}C_{y})_{2} alloys?
• Time-resolved optical conductivity and Higgs oscillations in two-band dirty superconductors
• Vortex rivers and multiple voltage transitions in superconducting MgB${}_2$ thin films