Related papers: Enhanced ferromagnetism from electron-electron int…
It is assumed that U atoms in $UGe_2$ have a number of $f$ electrons appropriate to give them each a spin $s=1$ as well as one extra itinerant electron which may equally well be on one or other U atom. The dynamical degrees of freedom are…
The role of electron-electron interactions on two-dimensional Dirac fermions remains enigmatic. Using a combination of nonperturbative numerical and analytical techniques that incorporate both the contact and long-range parts of the Coulomb…
We perform projective quantum Monte Carlo simulations of zigzag graphene nanoribbons within a realistic model with long-range Coulomb interactions. Increasing the relative strength of nonlocal interactions with respect to the on-site…
The coexistence of ferromagnetism and metallic conduction in doped manganites has long been explained by a double-exchange model in which the ferromagnetic exchange arises from the carrier hopping. We evaluate the zero-temperature spin…
Applying the local density and dynamical mean field approximations to paramagnetic \gamma-iron we revisit the problem of theoretical description of magnetic properties in a wide temperature range. We show that contrary to \alpha-iron, the…
In this work we present a model for the determination of the interaction energy for triplet and singlet states in atoms with incomplete filled shells. Our model includes the modification of the Coulomb's law by the interaction between the…
We compute the magnetic susceptibilities of interacting electrons in the presence of disorder on a two-dimensional square lattice by means of quantum Monte Carlo simulations. Clear evidence is found that at sufficiently low temperatures…
We consider the correction to conductivity of a 2D electron gas due to electron-electron interaction in the parallel magnetic field at arbitrary relation between temperature and the elastic mean free time. The correction exhibits…
The effects of interactions in a 2D electron system in a strong magnetic field of two degenerate Landau levels with opposite spins and at filling factors 1/2 are studied. Using the Chern-Simons gauge transformation, the system is mapped to…
We consider electronic correlation effects and their impact on magnetic properties of tetragonally distorted chemically ordered FeCo alloys (L1$_0$ structure) being a promising candidate for rare-earth-free permanent magnets. We employ a…
We generalize the classic N\'eel diagram for ferrimagnets within a mean-field framework and reveal a critical point at which full magnetic compensation is maintained below the Curie temperature and extends past the nominal compensation…
We explored the magnetic behavior of a common two-phase nanomagnetic system by Monte Carlo computer simulation of a modified Heisenberg model on a 3D complex lattice with single- and cluster-spins. The effect of exchange coupling between…
We present a numerical study based on Monte Carlo algorithm of the magnetic properties of a mixed Ising ferrimagnetic model on a cubic lattice where spins $\sigma =\pm 1/2$ and spins $S=0,\pm 1$ are in alternating sites on the lattice. We…
We consider the superconducting pairing induced by spin waves exchange in a ferromagnet with both conduction and localized electrons, the latter being described as spins. We use the microscopic Eliashberg theory to describe the pairing of…
We present a many-body approach to the electronic and magnetic properties of the (multiband) Kondo-lattice model with ferromagnetic interband exchange. The coupling between itinerant conduction electrons and localized magnetic moments…
We investigate the magnetism in tilted fermionic Mott insulators. With a small tilt, the fermions are still localized and form a Mott-insulating state, where the localized spins interact via antiferromagnetic exchange coupling. While the…
We report on Monte Carlo studies of the kinetic exchange model for (III,Mn)V ferromagnetic semiconductors in which S=5/2 local moments, representing Mn^{2+} ions, are exchange coupled to band electrons. We treat the Mn^{2+}$ spin…
We develop a numerical model that reproduces the thermal equilibrium and the spin transfer mechanisms in magnetic nanomaterials. We analyze the coherent two-particle spin exchange interaction and the electron-electron collisions. Our study…
One of the most active classes of nanostructures is Fullerene C$_{20}$, which has been exploited as an active component in significant applications. In this investigation, we used Monte Carlo simulations to investigate the magnetic and…
A novel method invented to measure the minute thermodynamic spin magnetization of dilute two dimensional fermions is applied to electrons in a silicon inversion layer. Interplay between the ferromagnetic interaction and disorder enhances…