相关论文: Quantum phase transition in one dimensional extend…
An effective Hamiltonian for the localized spins in the one-dimensional Kondo lattice model is derived via a unitary transformation involving a bosonization of delocalized conduction electrons. The effective Hamiltonian is shown to…
We study the two-dimensional Kondo lattice model with an additional Heisenberg exchange between localized spins. In a first step we use mean-field theory with two order parameters. The first order parameter is a complex pairing amplitude…
The one-dimensional Kondo lattice model with attractive interaction among the conduction electrons is analyzed in the case of half-filling. It is shown that there are three distinct phases depending on the coupling constants of the model.…
We present some preliminary results on the phase diagram of the 2D S=1/2 Kondo lattice model at finite doping. As a starting point the Hamiltonian is written in terms of local spin and charge excitations, and the interactions between these…
We describe the transition from a ferromagnetic phase, to a disordered para- magnetic phase, which occurs in one-dimensional Kondo lattice models with partial conduction band filling. The transition is the quantum order-disorder transition…
Low-energy properties of the one-dimensional Kondo lattice model are investigated by using bosonization and renormalization group methods. The formation of the spin and charge excitation gaps at half-filling is discussed in detail both for…
The Kondo lattice model introduced in 1977 describes a lattice of localized magnetic moments interacting with a sea of conduction electrons. It is one of the most important canonical models in the study of a class of rare earth compounds,…
Within a mean-field approximation, the ground state and finite temperature phase diagrams of the two-dimensional Kondo lattice model have been carefully studied as functions of the Kondo coupling $J$ and the conduction electron…
Using unitary transformations, we express the Kondo lattice Hamiltonian in terms of fermionic operators that annihilate the ground state of the interacting system and that represent the best possible approximations to the actual charged…
An integrable Kondo lattice model, which describes a strongly correlated electron host interacting with a spin-1/2 lattice, is proposed. It is found that with the variations of the Kondo coupling J, the hole concentration n_h and the…
We study the deconfined quantum critical point of the Kondo-Heisenberg lattice in three dimensions using a fermionic representation for the localized spins. The mean-field phase diagram exhibits a zero temperature quantum critical point…
We show that the Kondo chain away from half-filling has a spin gap upon the introduction of an additional direct Heisenberg coupling between localized spins. This is understood in the weak-Kondo-coupling limit of the Heisenberg-Kondo…
We study higher-spin ($S \geq 1$) generalization of the one-dimensional Kondo-Heisenberg model, in which the local spin-$S$ moments of the Kondo lattice model interact with each other via the antiferromagnetic Heisenberg interaction…
Topology, symmetry, electron correlations, and the interplay between them have formed the cornerstone of our understanding of quantum materials in recent years and are used to identify new emerging phases. While the first two give a fair…
We study the Kondo lattice model which is modified by the Holstein term, involving both the Kondo exchange coupling and the electron-phonon coupling constants, characterized by $J$ and $g$, respectively. The model is solved by employing the…
The quantum phase transition from a spin-Peierls phase with a small Fermi surface to a paramagnetic Luttinger-liquid phase with a large Fermi surface is studied in the framework of a one-dimensional Kondo-Heisenberg model that consists of…
The one-dimensional Kondo lattice model is investigated by using bosonization techniques and conformal field theory. In the half-filled band, the charge and spin gaps open for the anti-ferromagnetic Kondo coupling. Away from half-filling,…
The effect of next-nearest-neighbor hopping $t_{2}$ on the ground-state phase diagram of the one-dimensional Kondo lattice is studied with density-matrix renormalization-group techniques and by comparing with the phase diagram of the…
A spin-$\frac{1}{2}$ Kitaev sublattice interacting with a subsystem of spinless fermions is studied on a honeycomb lattice when the fermion band is half filled. The model Hamiltonian describes a topological Kondo lattice with the Kitaev…
We present an application of high-order series expansion in the coupling constants for the ground state properties of correlated lattice fermion systems. Expansions have been generated up to order $(t/J)^{14}$ for $d=1$ and $(t/J)^8$ for…