Related papers: New gap equation for a marginal Fermi liquid
The BCS-BEC crossover from strongly overlapping Cooper pairs to non-overlapping composite bosons in the strong coupling limit has been a long-standing issue of interacting many-body fermion systems. Recently, FeSe semimetal with hole and…
A layered superconductor with a full pairing energy gap can be driven into a nodal superconducting (SC) state by inter-layer pairing when the SC state becomes more quasi-3D. We propose that this mechanism is responsible for the observed…
The pairing of fermionic atoms in a mixture of atomic fermion and boson gases at zero temperature is investigated. The attractive interaction between fermions, that can be induced by density fluctuations of the bosonic background, can give…
We review recent theoretical progress in understanding spatially uniform $s$-wave superconductivity which arises from a fermion-fermion interaction, which is repulsive on the Matsubara axis, where it is real, but does depend on the…
We report the study on superconducting pairing mechanism of FeSe via the pair-breaking effects induced by H$^+$-irradiation combined with low-temperature specific heat measurements. A multi-gap structure with nodes or gap minima is…
Under the assumption that the superconducting state belongs to a single irreducible representation of lattice symmetry, we argue that the pairing symmetry in all measured iron-based superconductors is universally consistent with the A_{1g}…
We study the BCS energy gap $\Xi$ in the high-density limit and derive an asymptotic formula, which strongly depends on the strength of the interaction potential $V$ on the Fermi surface. In combination with the recent result by one of us…
We reconsider the fermion spectral function in the presence of the Cooper pair condensation and identified the interaction type of complex scalar and fermion, which gives consistent results with the expected s-wave superconductor for the…
Influence of the temperature dependent chemical potential on the condensation energy from a ternary Boson-Fermion model of superconductivity is reported, it consist of unbound electrons/holes which are fermions plus two-electron and…
In the two-component Fermi gas with a contact interaction, a pseudogap regime can exist at temperatures between the superfluid critical temperature $T_c$ and a temperature $T^* > T_c$. This regime is characterized by pairing correlations…
The ground-state superfluid behavior of ultracold atomic Fermi gases with a short-range attractive interaction in a quasi-two-dimensional Lieb lattice is studied using BCS mean-field theory, within the context of BCS-BEC crossover. We find…
This article is a review o over theory of superconductivity, which is constructed for systems with two overlapping energy bands at the Fermi surface and with arbitrary charge carrier density.There is taken into account all possible kinds of…
We consider a strongly repulsive fermionic gas in a two-dimensional optical lattice confined by a harmonic trapping potential. To address the strongly repulsive regime, we consider the $t-J$ Hamiltonian. The presence of the harmonic…
We study the normal state and pairing instability in electron-doped cuprates near optimal doping. We show that the fermionic self-energy has a non-Fermi liquid form leading to peculiar frequency dependencies of the conductivity and the…
We consider a Fermi gas with short-range attractive interactions that is confined along one direction by a tight harmonic potential. For this quasi-two-dimensional (quasi-2D) Fermi gas, we compute the pressure equation of state, radio…
We consider a very asymmetric system of Fermions with an interaction characterized by a positive scattering length only. The minority atoms pair and form a BEC of dimers, while the surplus fermions interact only indirectly through the…
We report an experimental study of quench dynamics across the superfluid transition temperature $T_c$ in a strongly interacting Fermi gas by ramping down the trapping potential. The nonzero quasi-condensate number $N_0$ at temperature…
In CaFe2As2, superconductivity can be achieved by applying a modest c-axis pressure of several kbar. Here we use scanning tunneling microscopy/spectroscopy (STM/S) to explore the STM tip pressure effect on single crystals of CaFe2As2. When…
Neutron crystal-field spectroscopy experiments in the Y- and La-type high-temperature superconductors HoBa2Cu3O6.56, HoBa2Cu4O8, and La1.81Sr0.15Ho0.04CuO4 are reviewed. By this bulk-sensitive technique, information on the gap function is…
We study the effects of an external periodic potential on the critical velocity of a superfluid Fermi gas in the crossover between the Bardeen-Cooper-Schrieffer (BCS) phase and Bose-Einstein condensation (BEC). We numerically solve the…