相关论文: Relationship between Pairing Symmetries and Intera…
Highly unconventional behavior of the thermodynamic response functions has been experimentally observed in a narrow gap semiconductor samarium hexaboride. Motivated by these observations, we use renormalization group technique to…
The iron-based superconductors allow for a zoo of possible order parameters due to their orbital degrees of freedom. These order parameters are often written in an orbital basis, as this allows to distinguish their different symmetry.…
We investigate the single-particle spectra of recently discovered kagome superconductors. We examine nine distinct superconducting pairing symmetries, including the uniform $s$-wave pairing function, nearest-neighbor and…
To explore whether a flat-band system can accommodate superconductivity, we consider repulsively interacting fermions on the diamond chain, a simplest quasi-one-dimensional system that contains a flat band. Exact diagonalization and the…
We carefully study how the fermion-fermion interactions affect the low-energy states of a two-dimensional spin-$1/2$ fermionic system on the kagom\'{e} lattice with a quadratic band crossing point. With the help of the renormalization group…
We employ a functional renormalization group approach to ascertain the pairing mechanism and symmetry of the superconducting phase observed in rhombohedral trilayer graphene. Superconductivity in this system occurs in a regime of carrier…
A major puzzle about the nature of the iron-based superconductivity appears in the case of the alkaline iron selenides. Compared to the iron pnictides, these systems have only electron Fermi pockets (i.e. no hole Fermi pockets) but…
We explore multiband effects on d-wave superconducting instabilities driven by electron-electron interactions. Our models on the two-dimensional square lattice consist of a main band with an extended Fermi surface and predominant weight…
Recent angle resolved photoemission spectroscopy(ARPES) experiments have suggested that BiS$_2$ based superconductors are at very low electron doping. Using random phase approximation(RPA) and functional renormalization group(FRG) methods,…
The functional renormalization group (RG) in combination with Fermi surface patching is a well-established method for studying Fermi liquid instabilities of correlated electron systems. In this article, we further develop this method and…
Using general arguments of an optimization taking place between the pair wave function and the repulsive part of the electron-electron interaction, we analyze the superconducting gap in materials with multiple Fermi-surface (FS) pockets,…
We studied the superconducting pairing symmetry based on a newly constructed tight-binding model of La$_3$Ni$_2$O$_7$ under pressure, where the $\gamma$ band sinks below the Fermi level and does not form the Fermi surface. The…
Motivated by a recent experiment of Song \emph{et al.} [Science {\bf 332}, 1410 (2011)], we theoretically study the spin dynamics, charge dynamics, and point-contact Andreev-reflection spectroscopy (PCARS) of two-band iron-based…
We present a renormalization group (RG) analysis of a fermionic "hot spot" model of interacting electrons on the square lattice. We truncate the Fermi surface excitations to linearly dispersing quasiparticles in the vicinity of eight hot…
We report the results of a parquet renormalization group (RG) study of competing instabilities in the full 2D four pocket, three orbital low-energy model for iron-based superconductors. We derive and analyze the RG flow of the couplings,…
For the newly discovered ironbased superconductors we propose a one band model for conduction band with first and secondnearestneighbor electron hoppings with two types of d wave and three types of s wave pairing symmetries for the…
Although correlated electronic-structure calculations explain very well the normal state of Sr$_2$RuO$_4$, its superconducting symmetry is still unknown. Here we construct the spin and charge fluctuation pairing interactions based on its…
It is shown that a generic form of an antiferromagnetic wave function opens strong electron-phonon coupling channels in the iron-based superconductors. In the nonmagnetic state these channels exist locally on a single iron atom, but are…
Motivated by the experimental detection of superconductivity in the low-carrier density half-Heusler compound YPtBi, we study the pairing instabilities of three-dimensional strongly spin-orbit coupled semimetals with a quadratic band…
We analyze the competition between antiferromagnetism and superconductivity in the two-dimensional Hubbard model by combining a functional renormalization group flow with a mean-field theory for spontaneous symmetry breaking. Effective…