相关论文: Fermionic Atoms in Optical Superlattices

We consider the possibility that instabilities of the Abrikosov-Suhl resonance lead to new fixed point behavior of the Kondo effect in a lattice environment. In one scenario, a pairing component to the resonant scattering develops in the…

We carefully consider the interplay between ferromagnetism and the Kondo screening effect in the conventional Kondo lattice systems at finite temperatures. Within an effective mean-field theory for small conduction electron densities, a…

We analyze a microscopic mechanism behind coexistence of a heavy Fermi liquid and geometric frustration in Kondo lattices. We consider a geometrically frustrated periodic Anderson model and demonstrate how orbital fluctuations lead to a…

While standard heavy fermion metals feature a single spin-1/2 local moment per unit cell, more complicated systems with multiple distinct local moments have been synthesized as well, with Ce_3Pd_20(Si,Ge)_6 being one example. Here, we…

A review is given of the experimental situation and theoretical predictions concerning unconventional magnetic ordering in dense Kondo 4f- and 5f-systems, including recently investigated on cerium, ytterbium, and actinide based ternary…

We investigate states of fermionic atoms across a broad Feshbach resonance in an optical superlattice which allows interaction only among a small number of lattice sites. The states are in general described by superpositions of atomic…

We consider the potential for novel forms of magnetism arising from the subtle interplay between electrons and spins in the under-screened kagome Kondo lattice model. At weak coupling, we show that incommensurate non-coplanar multi-wave…

Electronic flat bands represent a paradigmatic platform to realize strongly correlated matter due to their associated divergent density of states. In common instances, including electron-electron interactions leads to magnetic instabilities…

We apply the extended (statistically-consistent, SGA) Gutzwiller-type approach to the periodic Anderson model (PAM) in an applied magnetic field and in the strong correlation limit. The finite-U corrections are included systematically by…

Highly accurate numerical results for single-particle spectrum and order parameter are obtained for the magnetically ordered Kondo lattice by means of the dynamical mean-field theory combined with the continuous-time quantum Monte Carlo…

We study magnetic ordering of an extended Kondo-lattice model including an additional on-site Coulomb interaction between the itinerant states. The model is solved in the dynamical mean-field theory using Wilson's numerical renormalization…

The one dimensional Kondo lattice model is investigated using Quantum Monte Carlo and transfer matrix techniques. In the strong coupling region ferromagnetic ordering is found even at large band fillings. In the weak coupling region the…

The interplay of magnetic energies in a Kondo lattice is the underlying physics of a heavy fermion system. Creating an artificial Kondo lattice system by localizing the moments in an ordered metallic array provides a prototype system to…

The competition between spin glass, ferromagnetism and Kondo effect is analysed here in a Kondo lattice model with an inter-site random coupling $J_{ij}$ between the localized magnetic moments given by a generalization of the Mattis model…

We study the atom-light interaction in the fully quantum regime, with focus on off-resonant light scattering into a cavity from ultracold atoms trapped in an optical lattice. The detection of photons allows the quantum nondemolition (QND)…

Ultrafast optical spectroscopy was used to investigate the ultrafast quasiparticle dynamics of antiferromagnetic Kondo lattice CeAuSb$_2$ as a function of temperature and fluence. Our results reveal (i) the opening of a narrow hybridization…

The one dimensional dilute Kondo lattice model is investigated by means of bosonization for different dilution patterns of the array of impurity spins. The physical picture is very different if a commensurate or incommensurate doping of the…

Near zero temperature, quantum magnetism can non-trivially arise from short-range interactions, but the occurrence of magnetic order depends crucially on the interplay of interactions, lattice geometry, dimensionality and doping. Even…

We develop a microscopic theory of the single impurity Kondo effect on a metallic surface. We calculate the hybridization energies for the Anderson Hamiltonian of a magnetic impurity interacting with surface and bulk states and show that,…

The Fermi-Hubbard model is a key concept in condensed matter physics and provides crucial insights into electronic and magnetic properties of materials. Yet, the intricate nature of Fermi systems poses a barrier to answer important…