Related papers: Ferromagnetism in the Extended Periodic Anderson M…
We introduce a novel mechanism for itinerant ferromagnetism, which is based on a simple two-band model, and using numerical and analytical methods, we show that the Periodic Anderson Model (PAM) contains this mechanism. We propose that the…
We introduce a novel mechanism for itinerant ferromagnetism, based on a simple two-band model. The model includes an uncorrelated and dispersive band hybridized with a second band which is narrow and correlated. The simplest Hamiltonian…
By nonperturbatively solving the nonequilibrium Anderson two-impurity model with the hierarchical equations of motion approach, we report a robust ferromagnetic (FM) phase in series-coupled double quantum dots, which can suppress the…
We compare different approximation schemes for investigating ferromagnetism in the periodic Anderson model. The use of several approximations allows for a detailed analysis of the implications of the respective methods, and also of the…
Using the constrained-path Monte Carlo method, we studied the magnetic properties of the two-dimensional periodic Anderson model for electron fillings between 1/4 and 1/2. We also derived two effective low energy theories to assist in…
Heavy fermion materials are compounds in which localized $f$-orbitals hybridize with delocalized $d$ ones, leading to quasiparticles with large renormalized masses. The presence of strongly correlated $f$-electrons at the Fermi level may…
We studied magnetic properties of the double exchange (DE) model with S=1/2 localized spins at T=0, using exact diagonalization in the framework of the dynamical mean field theory. Obtained phase diagram contains ferromagnetic,…
We study ferromagnetism in the periodic Anderson model with and without a magnetic field by the Gutzwiller theory. We find three ferromagnetic phases: a weak ferromagnetic phase (FM0), a half-metallic phase without Fermi surface for the…
We have investigated the valence transition in the extended periodic Anderson model (EPAM) within the framework of dynamical mean field theory. Previous theoretical studies have indicated the presence of this transition in parameter ranges…
We introduce a new aproximation scheme for the periodic Anderson model (PAM). The modified alloy approximation represents an optimum alloy approximation for the strong coupling limit, which can be solved within the CPA-formalism.…
A large class of correlated quantum materials feature strong Hund's coupling. Yet cold-atom quantum simulators have so far focused primarily on single-orbital Fermi-Hubbard systems near a Mott insulator. Here we show that repulsively…
}We present a formalism for extending the second moment tight-binding model, incorporating ferro- and anti-ferromagn etic interaction terms which are needed for the FeCr system. For antiferromagnetic and paramagnetic materials, an explicit…
We introduce a new approach to the periodic Anderson model (PAM) that allows a detailed investigation of the magnetic properties in the Kondo as well as the intermediate valence regime. Our method is based on an exact mapping of the PAM…
This work presents a comprehensive theoretical investigation of magnon-phonon-photon interactions in cubic ferromagnets near orientational phase transitions (OPT). The study focuses on the interplay of magnetoelastic (ME),…
We consider a Periodic Anderson Model (PAM) with a momentum-dependent inter-band hybridization that is strongly suppressed near the Fermi level. Under these conditions, we reduce the PAM to an effective low-energy Hamiltonian, $H_{\rm…
We study the quantum phase transition in $f$-electron systems as a quantum Lifshitz transition driven by selective Mott localization in a realistic extended Anderson lattice model. Using DMFT, we find that a quantum critical {\it phase}…
We investigate the competition of the Kondo and the RKKY interactions in heavy fermion systems. We solve a periodic Anderson model using Extended Dynamical Mean Field Theory (EDMFT) with QMC. We monitor simultaneously the evolution of the…
Starting with an extended version of the Anderson lattice where the f-electrons are allowed a weak dispersion, we examine the possibility of a Mott localization of the f-electrons, for a finite value of the hybridization $V$. We study the…
A double-exchange mechanism for the emergence of ferromagnetism in cubic uranium compounds is proposed on the basis of a $j$-$j$ coupling scheme. The idea is {\it orbital-dependent duality} of $5f$ electrons concerning itinerant…
We investigate the location and nature of the para-ferro transition of interacting electrons in dispersionless bands using the example of the Hubbard model on the Tasaki lattice. This case can be analyzed as a geometric site-percolation…