相关论文: Singular Fermi Surfaces II. The Two--Dimensional C…

The key feature of the Fe-based superconductors is their quasi 2D multiband Fermi surface. By relating the problem to a negative U Hubbard model and its superconducting ground state, we show that the defining instability of such a Fermi…

Recently a debate has arisen over which of the two distinct parts of the Fermi surface of Sr2RuO4, is the active part for the chiral p-wave superconductivity. Early theories proposed p-wave pairing on the two dimensional gamma-band, while a…

We study the occurrence and the origin of ferromagnetic fluctuations in the longitudinal spin susceptibility of the $t$-$t'$-Rashba-Hubbard model on the square lattice. The combined effect of the second-neighbor hopping $t'$ and the…

The appearance of van Hove singularities near the Fermi level leads to prominent phenomena, including superconductivity, charge density wave, and ferromagnetism. Here a bilayer Kagome lattice with multiple van Hove singularities is designed…

We investigate the quasiparticle spectrum near surfaces in a two-dimensional system with d-density-wave order within a mean-field theory. For Fermi surfaces with perfect nesting for the ordering wave vector of the d-density-wave, a zero…

We report on the interplay between a van Hove singularity and a charge density wave state in 2H-TaSe$_{2}$. We use angle-resolved photoemission spectroscopy to investigate changes in the Fermi surface of this material under surface doping…

We consider Friedel oscillation in the two-dimensional Dirac materials when Fermi level is near the van Hove singularity. Twisted graphene bilayer and the surface state of topological crystalline insulator are the representative materials…

First principles density functional calculations of the electronic and magnetic properties of spinel-structure LiV$_{2}$O$_{4}$ have been performed using the full potential linearized augmented planewave method. The calculations show that…

The effect of strong anisotropy on the Fermi line of a system of correlated electrons is studied in two space dimensions, using renormalization group techniques. Inflection points change the scaling exponents of the couplings, enhancing the…

de Haas-van Alphen oscillation spectrum of two-dimensional systems is studied for general power law energy dispersion, yielding a Fermi surface area of the form $S(E)\propto E^\alpha$ for a given energy $E$. The case $\alpha=1$ stands for…

We perform a variational Monte Carlo study on spontaneous d-wave form Fermi surface deformation ($d$FSD) within the three-band Hubbard model. It is found that the variational energy of a projected Fermi sea is lowered by introducing an…

We uncover the properties of complex tensor (d-wave) superconducting order in three-dimensional Rarita-Schwinger-Weyl semimetals that host pseudospin-3/2 fermions at a fourfold linear band crossing point. Although the general theory of…

To assess the strength of nematic fluctuations with a finite wave vector in a two-dimensional metal, we compute the static d-wave polarization function for tight-binding electrons on a square lattice. At Van Hove filling and zero…

We study the low energy effective theory for a non-Fermi liquid state in 2+1 dimensions, where a transverse U(1) gauge field is coupled with a patch of Fermi surface with N flavors of fermion in the large N limit. In the low energy limit,…

Recent experimental data for the overdoped LSCO have firmly established the properties which characterize the transition between the superconducting and the Fermi liquid metallic phases. The thermodynamic response functions show a…

The properties of correlated electron materials are often intricately linked to Van Hove singularities (VHS) in the vicinity of the Fermi energy. The class of these VHS is of great importance, with higher-order ones -- with power-law…

It is shown that the energy $(\varepsilon)$ and momentum $(k)$ dependences of the electron self-energy function $ \Sigma (k, \varepsilon + i0) \equiv \Sigma^{R}(k, \varepsilon) $ are, $ {\rm Im} \Sigma^{R} (k, \varepsilon) =…

We have performed high energy resolution angle-resolved photoemission studies of the normal state band structure of oxygen overdoped $Bi_{2}Sr_{2}Ca_{1}Cu_{2}O_{8+x}$. We find that there is an extended saddle point singularity in the…

The electronic structure of WTe$_2$ and orthorhombic $\gamma-$MoTe$_2$, are claimed to contain pairs of Weyl type-II points. A series of ARPES experiments claim a broad agreement with these predictions. We synthesized single-crystals of…

(1) The temperature dependence of the specific heat for a marginal Fermi liquid has been calculated. (2) We calculated the self-energy at T=0 for a two dimensional fermionic system with hyperbolic dispersion. The existence of the saddle…