Related papers: Bogoliubov Quasiparticle on the Gossamer Fermi Sur…
We discuss a close relationship between a quasiparticle on the Bogoliubov Fermi surface and an odd-frequency Cooper pair in a superconductor in which a Cooper pair consisting of two j=3/2 electrons forms the pseudospin-quintet even-parity…
The pseudogap phenomena have been a long-standing mystery of the cuprate high-temperature superconductors. The pseudogap in the electron-doped cuprates has been attributed to band folding due to antiferromagnetic (AFM) long-range order or…
Numerical study of momentum-dependent gap function is presented to make clear the origin of superconductivity in copper oxides. We claim that antinodal region with pronounced nesting feature of the Fermi contour gives rise to…
Correlation effects in CuO$_2$ layers give rise to a complicated landscape of collective excitations in high-T$_{\rm c}$ cuprates. Their description requires an accurate account for electronic fluctuations at a very broad energy range and…
Superconductivity is achieved by the pairing of electrons and phase coherence between the Cooper pairs. According to the Bardeen-Cooper-Schrieffer theory, the quasiparticles with Bogoliubov dispersion exists and reveal particle-hole…
The study of the iron-based superconductor, FeSe, has resulted in various topics, such as the interplay among superconductivity, nematicity, and magnetism, Bardeen-Cooper-Schrieffer Bose-Einstein-condensation (BCS-BEC) crossover, and…
The Cooper pairing mechanism of heavy-fermion superconductors, while long hypothesized as due to spin fluctuations, has not been determined. It is the momentum space (k-space) structure of the superconducting energy gap delta(k) that…
We apply the spin-fermion model to study the normal state and pairing instability in electron-doped cuprates near the antiferromagnetic QCP. Peculiar frequency dependencies of the normal state properties are shown to emerge from the…
S-substituted FeSe superconductors in the tetragonal phase display several unique features among iron-based superconductors, particularly the presence of zero-energy excitations in the superconducting (SC) state. The recent concept of…
Electronic Raman scattering measurements have been performed on hole doped copper oxide superconductors as a function of temperature and doping level. In the superconducting state coherent Bogoliubov quasiparticles develop preferentially…
We model the pseudogap state of the hole- and electron-doped cuprates as a metal with hole and/or electron pocket Fermi surfaces. In the absence of long-range antiferromagnetism, such Fermi surfaces violate the Luttinger requirement of…
The momentum dependence of the low energy quasiparticle spectrum and the related Bogoliubov angle in cuprate superconductors are studied within the kinetic energy driven superconducting mechanism. By calculation of the ratio of the low…
We model the underdoped cuprates using fermions moving in a background with local antiferromagnetic order. The antiferromagnetic order fluctuates in orientation, but not in magnitude, so that there is no long-range antiferromagnetism, but a…
It was recently understood that centrosymmetric multiband superconductors that break time-reversal symmetry generically show Fermi surfaces of Bogoliubov quasiparticles. We investigate the thermodynamic stability of these Bogoliubov Fermi…
Development of the STM and ARPES spectroscopies enabled to reach the resolution level sufficient for detecting the particle-hole entanglement in superconducting materials. On a quantitative level one can characterize such entanglement in…
Noise spectroscopy is a key technique to investigate the nature and dynamics of charge carriers in superconductors. The recently discovered superconducting hybrids with Bogoliubov Fermi surfaces exhibit a particularly intriguing and rich…
Angle-resolved photoemission on underdoped La$_{1.895}$Sr$_{0.105}$CuO$_4$ reveals that in the pseudogap phase, the dispersion has two branches located above and below the Fermi level with a minimum at the Fermi momentum. This is…
The emergence of the coherent quasiparticle peak and the development of the peak-dip-hump structure in the anti-nodal region below $T_{c}$ is the most prominent non-BCS signature of the underdoped high-$T_{c}$ cuprates, in which no coherent…
We study pseudogap phenomena and Fermi-arc formation experimentally observed in typical two dimensional doped Mott insulators, namely, underdoped cuprate superconductors. To develop a physically unequivocal theory, we start from the…
Electron interactions are pivotal for defining the electronic structure of quantum materials. In particular, the strong electron Coulomb repulsion is considered the keystone for describing the emergence of exotic and/or ordered phases of…