Related papers: Exchange interaction between $J$-multiplets
We calculate the density-dependent spin-isospin asymmetry energy $J(k_f)$ of nuclear matter in the three-loop approximation of chiral perturbation theory. The interaction contributions to $J(k_f)$ originate from one-pion exchange, iterated…
The double-exchange model for the Mn oxides with orbital degeneracy is studied with including on-site Coulomb repulsion, Jahn-Teller (J-T) coupling and doping-induced disorder. In the strong interaction limit, it is mapped onto a…
We perform time-dependent simulations of spin exchange for an electron pair in laterally coupled quantum dots. The calculation is based on configuration interaction scheme accounting for spin-orbit (SO) coupling and electron-electron…
We study the $\pm J$ three-dimensional Ising model with a longitudinal anisotropic bond randomness on the simple cubic lattice. The random exchange interaction is applied only in the $z$ direction, whereas in the other two directions, $xy$…
We present a technique to map an electronic model with local interactions (a generalized multi-orbital Hubbard model) onto an effective model of interacting classical spins, by requiring that the thermodynamic potentials associated to spin…
We determine the spin exchange coupling J between two electrons located in two vertically tunnel-coupled quantum dots, and its variation when magnetic (B) and electric (E) fields (both in-plane and perpendicular) are applied. We predict a…
A treatment of many-electron polar and $s-d(f)$ exchange models is carried out in connection with the development of the theory of magnetism of transition and rare-earth metals, as well as their compounds. Particular emphasis is placed on…
We present an approach based on the dynamical mean field theory which is able to give the excitation spectrum of a triply degenerate Hubbard model with a Hund's exchange invariant under spin rotation. The lattice problem can be mapped onto…
Similarly to their purely electric counterparts, spintronic circuits may be presented as networks of lumped elements. Due to interplay between spin and charge currents, each element is described by a matrix conductance. We establish…
Quantum rings can be characterized by a specific radius and ring width. For this rich class of physical systems, an accurate approximation for the exchange-hole potential and thus for the exchange energy is derived from first principles.…
We develop a comprehensive description of static and dynamic spin-transfer torque at interfaces between a normal metal and a magnetic material. Specific examples of the latter include ferromagnets, collinear and noncollinear…
This thesis uses a quantity that is defined and justified by information theory -- mutual information -- to examine models of condensed matter systems. More precisely, it studies models which are made up out of ferromagnetically interacting…
The exchange interaction between two magnetic moments embedded in a host metal is fundamental to the description of the magnetic behavior of solids. In the standard spin-degenerate electron gas, it leads to the well known…
The effect of antiferromagnetic spin fluctuations on two-dimensional quarter-filled systems is studied theoretically. An effective $t-J'-V$ model on a square lattice which accounts for checkerboard charge fluctuations and…
The spin-orbit interaction in semiconductors is shown to result in an anisotropic contribution into the exchange Hamiltonian of a pair of localized conduction-band electrons. The anisotropic exchange interaction exists in semiconductor…
The recent development in the field of 2D magnetic materials urges reliable theoretical methodology for determination of magnetic properties. Among the available methods, ab initio four-state energy mapping based on Density Functional…
We explore the control and switching of the entangled spin states of multi-spin particle qubit coupled to an electron using a three-particle spin model described by $S_i$ ($i=1,2,3$), in which $S_1=\tfrac{1}{2}$ is an electron and $S_{2,3}$…
We studied the exchange coupling and decoupling occurring in a nanocomposite spin system based on a 3D Heisenberg model by means of Monte Carlo numerical computation simulation. Different from conventional micromagnetism approach which…
The method developed in [L. P. Gor'kov and L. P. Pitaevskii, Sov. Phys. Dokl. 8, 788 (1964); C. Herring and M. Flicker, Phys. Rev. 134, A362 (1964)] to calculate the asymptotic form of exchange interactions between hydrogen atoms in the…
We investigate the far-from-equilibrium nature of magnetic anisotropy and exchange interactions between molecular magnets embedded in a tunnel junction. By mapping to an effective spin model, these magnetic interactions can be divided into…