Related papers: Dispersion kinks from electronic correlations in a…
We present a theoretical model which accounts for recent angle resolved photoemission data in bilayer cuprate superconductors. Lineshapes and dispersions of the various bonding and antibonding features in the spectra are quantitatively…
Recent observation of a "kink" in single-particle dispersion in photoemission experiments on cuprate superconductors has initiated a heated debate over the issue of a boson that mediates the pairing in cuprates. If the "kink" is indeed…
It is proposed that the 50-70 meV dispersion anomaly (kink) in electron-doped cuprates revealed by recent angle-resolved photoemission spectroscopy experiments is caused by coupling with the spin fluctuation. We elaborate that the kink…
Ultrahigh resolution angle-resolved photoemission spectroscopy with low-energy photons is used to study the detailed momentum dependence of the well-known nodal "kink" dispersion anomaly of Bi2Sr2CaCu2O8+{\delta}. We find that the kink's…
In the present photoemission study of a cuprate superconductor Bi1.74Pb0.38Sr1.88CuO6+delta, we discovered a large scale dispersion of the lowest band, which unexpectedly follows the band structure calculation very well. The incoherent…
We present direct experimental evidence of a weakly coupled multiband superconducting state in the bilayer iron-based superconductor ACa$_2$Fe$_4$As$_4$F$_2$ (A = K, Cs) via ultrahigh-resolution angle-resolved photoemission spectroscopy…
We study the behavior of Dirac fermions in the presence of electron correlation in a nonsymmorphic Kondo lattice system, CeAgSb2 employing high-resolution angle-resolved photoemission spectroscopy and first-principles calculations.…
Based on experimental data on the newly synthesized iron-based superconductors and the relevant band structure calculations, we propose a minimal two-band BCS-type Hamiltonian with the interband Hubbard interaction included. We illustrate…
The renormalization of the electrons in cuprate superconductors is characterized by the kink in the quasiparticle dispersion. Here the bilayer coupling effect on the quasiparticle dispersion kink in the electron-doped bilayer cuprate…
Superconductivity is a remarkably widespread phenomenon observed in most metals cooled down to very low temperatures. The ubiquity of such conventional superconductors, and the wide range of associated critical temperatures, is readily…
The band structure of iron-based superconductors gives rise to yet another scenario for the appearance of Dirac fermions. A viewpoint on "Observation of Dirac cone electronic dispersion in BaFe2As2" (Richard et.al., PRL 104, 137001 (2010)).
Magnetically mediated Cooper pairing is generally regarded as a key to establish the unified mechanism of unconventional superconductivity. One crucial evidence is the neutron spin resonance arising in the superconducting state, which is…
We report quasiparticle properties of the half-metal ferromagnet CrO2 by means of high-resolution angle-resolved photoemission spectroscopy (ARPES). We clearly observed the Fermi surface (FS) and band dispersion in good agreement with the…
Understanding the formation of Cooper pairs in iron-based superconductors is one of the most important topics in condensed matter physics. In conventional superconductors, the electron-phonon interaction leads to the formation of Cooper…
Based on an effective two-band model and using the fluctuation-exchange (FLEX) approach, we explore spin fluctuations and unconventional superconducting pairing in Fe-based layer superconductors. It is elaborated that one type of interband…
The varying metallic antiferromagnetic correlations observed in iron-based superconductors are unified in a model consisting of both itinerant electrons and localized spins. The decisive factor is found to be the sensitive competition…
We argue that the shape of the dispersion along the nodal and antinodal directions in the cuprates can be understood as a consequence of the interaction of the electrons with collective spin excitations. In the normal state, the dispersion…
In cuprate superconductors, electron-electron repulsion results in characteristic spectroscopic features known as `waterfalls', where the sharp quasiparticle dispersion transitions into broad Hubbard bands. However, in multi-orbital…
The Josephson-like interband couplings in multi-band superconductivity exhibit degenerate energy minima, which support states with kinks in phase of superconductivity. When the interband couplings in systems of three or more components are…
We performed a Laser angle-resolved photoemission spectroscopy (ARPES) study on a wide doping range of Ba1-xKxFe2As2 (BaK) iron-based superconductor. We observed a robust low-binding energy (BE) kink structure in the dispersion which is…