Related papers: Electronic structure and resistivity of the double…
Previously a many-body coherent potential approximation (CPA) was used to study the double exchange (DE) model with quantum local spins S, both for S=1/2 and for general S in the paramagnetic state. This approximation, exact in the atomic…
Density-functional studies of the electronic structures and exchange interaction parameters have been performed for a series of ferromagnetic full Heusler alloys of general formula Co$_2$MnZ (Z = Ga, Si, Ge, Sn), Rh$_2$MnZ (Z = Ge, Sn, Pb),…
This paper is a brief review of our recent studies concerning on magnetism and electronic states of lattice systems with Hund coupling. First we examined the effectiveness of the Hund coupling in realizing ferromagnetism in the doubly…
Electronic structure calculations are routinely carried out within the framework of density-functional theory, often with great success. For electrons in reduced dimensions, however, there is still a need for better approximations to the…
A Hubbard-like model with SU(4) symmetry for electrons with two-fold orbital degeneracy is studied extensively. Exact solution in one dimension is derived by means of Bethe ansatz, where the sites are supposed to be occupied by at most two…
We study the electronic structure of graphene with a single substitutional vacancy using a combination of the density-functional, tight-binding, and impurity Green's function approaches. Density functional studies are performed with the…
We theoretically investigate the ground state magnetic properties of the brownmillerite phase of SrCoO2.5. Strong correlations within Co d electrons are treated within the local spin density approximations of Density Functional theory (DFT)…
Calculations of one-electron spectral functions, optical conductivity and spin-wave energy in the Holstein double-exchange model are made using the many-body coherent potential approximation. Satisfactory agreement is obtained with…
The Kondo-lattice model is well established as a method to describe an exchange coupling between single conduction electrons and localized magnetic moments. As a nontrivial exact result the zero-bandwidth limit (atomic limit) can be used to…
The double exchange (DE) model is systematically applied for studying the coupling between ferroelectric (FE) and magnetic orders in several prototypical types of multiferroic manganites. The model was constructed for the magnetically…
Using spin-density-functional theory, we study the electronic states of a two-dimensional parabolic quantum dot with up to N=58 electrons. We observe a shell structure for the filling of the dot with electrons. Hund's rule determines the…
The band structure and magnetotransport of a two-dimensional electron gas (2DEG), in the presence of the Rashba (RSOI) and Dresselhaus (DSOI) terms of the spin-orbit interaction and of a perpendicular magnetic field, is investigated. Exact…
In this paper, we investigate the open tight-binding model with $N$ sites coupled to two reservoirs on its edges with the nonequilibrium Green function method to understand effects of open boundaries. As a result, we obtain an analytical…
In response to the experimental discovery of double perovskite Ru- base material, The magnetic and electronic properties of the double exchange mechanism are studied theoretically. The electron band structure and the spin wave spectrum…
We provide a quantitative description of the structure of edge states in split-gate quantum wires in the integer quantum Hall regime. We develop an effective numerical approach based on the Green's function technique for the self-consistent…
Using the strong coupling diagram technique for calculating the electron Green's function of the two-dimensional Hubbard model we have summed infinite sequences of ladder diagrams, which describe interactions of electrons with spin and…
We have studied the ground state structure of quantum strips within the local spin-density approximation, for a range of electronic densities between $\sim$ 5$\times10^4$ and 2$\times10^6$ cm$^{-1}$ and several strengths of the lateral…
The influence of electronic structure evolution upon pressure on the temperature dependencies of electrical resistivity of pure Np, Pu, Am, and Cm metals have been investigated within coherent potential approximation (CPA) for many-bands…
We have used the Kubo formula to calculate the temperature dependence of the electrical conductance of the double exchange Hamiltonian. We average the conductance over an statistical ensemble of clusters, which are obtained by performing…
We introduce the idea that the electronic band structure of a charge density wave system may mimic the electronic structure of graphene. In that case a class of materials quite different from graphene might be opened up to exploit…