相关论文: Dirac fermions and Kondo effect
The Kondo effect, a hallmark of many-body physics, emerges from the antiferromagnetic coupling between localized spins and conduction fermions, leading to a correlated many-body singlet state. Here we propose to use the mixed-dimensional…
We derive a solvable resonant-level type model, to describe an impurity spin coupled to zero-energy bound states localized at the edge of a one dimensional d-wave superconductor. This results in a two-channel Kondo effect with a quite…
We use determinant quantum Monte Carlo (DQMC) simulations to study the role of electron-electron interactions on three-dimensional (3D) Dirac fermions based on the $\pi$-flux model on a cubic lattice. We show that the Hubbard interaction…
The Kondo effect, an eminent manifestation of many-body physics in condensed matter, is traditionally explained as exchange scattering of conduction electrons on a spinful impurity in a metal. The resulting screening of the impurity's local…
We investigate the Kondo effect in two-dimensional disordered electron systems using a finite-temperature quantum Monte Carlo method. Depending on the position of a magnetic impurity, the local moment is screened or unscreened by the spin…
A low-energy theory for the helical metallic states, residing on the surface of cubic topological Kondo insulators, is derived. Despite our analysis being primarily focused on a prototype topological Kondo insulator, Samarium hexaboride…
We propose that the thermoelectric power distinguishes two competing scenarios for quantum phase transitions in heavy fermions : the spin-density-wave (SDW) theory and breakdown of the Kondo effect. In the Kondo breakdown scenario, the…
We study the Kondo-Heisenberg model using a fermionic representation for the localized spins. The mean-field phase diagram exhibits a zero temperature quantum critical point separating a spin liquid phase where the f-conduction…
We study theoretically the behavior of thermal massless Dirac fermions inside graphene-based Ferromagnetic/Insulator/d-wave (s-wave) superconductor (F/I/d and F/I/S) junctions in the ballistic regime. Using the Dirac-BdG wave functions…
The scattering of Dirac fermions on the sine-Gordon kink is studied both analytically and numerically. To achieve invariance with respect to a discrete symmetry, the sine-Gordon model is treated as a nonlinear $\sigma$-model with a circular…
The formation of a heavy Fermi liquid in metals with local moments is characterized by multiple energy and temperature scales, most prominently the Kondo temperature and the coherence temperature, characterizing the onset of Kondo screening…
We present theoretical results for the underscreened Kondo lattice model with localized S=1 spins coupled to a conduction band through a Kondo coupling, $J_K$, and interacting among them ferromagnetically. We use a fermionic representation…
The Kondo effect involves the formation of a spin singlet by a magnetic impurity and conduction electrons. It is characterized by a low temperature scale, the Kondo temperature, $T_K$, and an associated long length scale, $\xi_K = \hbar…
Recently, a series of noncentrosymmetric superconductors has been a subject of considerable interest since the discovery of superconductivity in CePt_3Si. In noncentrosymmetric materials, the degeneracy of bands is lifted in the presence of…
We propose a novel mechanism of the Kondo effect driven by a chirality imbalance (or chiral chemical potential) of relativistic light fermions. This effect is realized by the mixing between a right- or left-handed fermion and a heavy…
Based on a local mean-field theory approach at Anderson localization, we find a distribution function of critical temperature from that of disorder. An essential point of this local mean-field theory approach is that the information of the…
The Kondo effect is a striking consequence of the coupling of itinerant electrons to a quantum spin with degenerate energy levels. While degeneracies are commonly thought to arise from symmetries or fine-tuning of parameters, the recent…
Using exact-diagonalization of small clusters and Dyson equation embedding techniques, the conductance $G$ of linear arrays of quantum dots is investigated. The Hubbard interaction induces Kondo peaks at low temperatures for an odd number…
Moir\'e structures, along with line-graph-based $d$-electron systems, represent a setting to realize flat bands. One form of the associated strong correlation physics is the Kondo effect. Here, we address the recently observed Kondo-driven…
We investigate Dirac fermions in the antifferomagnetic metallic state of iron-based superconduc- tors. Deriving an effective Hamiltonian for Dirac fermions, we reveal that there exist two Dirac cones carrying the same chirality, contrary to…