Related papers: Spin Diffusion in Double-Exchange Manganites
The physics of ferromagnetic doped manganites, such as \chem{La_{1-x}Ca_xMnO_3} with $x\approx0.2$--0.4, is reviewed. The concept of double exchange is discussed within the general framework of itinerant electron magnetism. The new feature…
A recent, major, puzzle in the core-level photoemission spectra of doped manganites is the observation of a 1-2 eV wide shoulder with intensity varying with temperature T as the square of the magnetization over a T scale of order 200K, an…
The surface magnetic phase transition of a double-exchange model for metallic manganites is studied using a Schwinger-boson mean-field method. About three unit-cells wide surface layers are identified. The magnetic moment in these layers…
his study is an investigation of spin wave spectrum in macrostructures composed of two ferromagnetic materials and showing a 3D periodicity: spherical ferromagnetic grains disposed in the nodes of a 3D crystal lattice are embedded in a…
The electron tunneling in half metallic manganite tunnel junctions is studied by using a quantum mechanically treated double exchange model. We show that the stimulation of spin excitations, caused by the strong Hund's coupling between the…
We present a theory of out-of-equilibrium ultrafast spin dynamics in magnetic heterostructures based on the s-d model of ferromagnetism. Both in the bulk and across interfaces, the exchange processes between the itinerant s and the…
Monte-Carlo simulations and ground-state calculations have been used to map out the phase diagram of a system of classical spins, on a simple cubic lattice, where nearest-neighbor pairs of spins are coupled via competing antiferromagnetic…
A complete set of the generalized drift-diffusion equations for a coupled charge and spin dynamics in ferromagnets in the presence of extrinsic spin-orbit coupling is derived from the quantum kinetic approach, covering major transport…
We show within the dynamical mean field theory that local multiplet interactions such as Hund's rule coupling produce local pairing superconductivity in the strongly correlated regime. Spin-triplet superconductivity driven by the Hund's…
The spin dynamics of stripes in high-temperature superconductors and related compounds is studied in the framework of a spin-wave theory for a simple spin-only model. The magnon dispersion relation and the magnetic structure factor are…
Elastic and inelastic neutron scattering was used to study two ferromagnetic manganites A$_{1-x}$B$_{x}$MnO$_3$ (x $\approx$ 0.3) with $T_c$=197.9 K and 300.9 K. The spin dynamical behavior of these is similar at low temperatures, but…
We investigate the influence of an interband exchange interaction on magnetism in a two-band Hubbard model. Our main emphasis lies on spin-flip scattering which is often neglected but is neccessary to retain the full rotational symmetry of…
We derive a drift-diffusion equation for spin polarization in semiconductors by consistently taking into account electric-field effects and nondegenerate electron statistics. We identify a high-field diffusive regime which has no analogue…
We present a theoretical framework for evaluating effective interactions between localized spins mediated by itinerant electrons in double-exchange models. Performing the expansion with respect to the spin-dependent part of the electron…
Ferromagnetic (FM) manganites, a group of likely half-metallic oxides, are of special interest not only because they are a testing ground of the classical doubleexchange interaction mechanism for the colossal magnetoresistance, but also…
This article gives a comprehensive review on the recent studies of the double exchange systems using non-perturbative approaches; the dynamical mean-field theory and the Monte Carlo method. Investigations beyond mean-field type treatments…
We consider the square lattice Heisenberg antiferromagnet with plaquette ring exchange and a finite interlayer coupling leading to a consistent description of the spin-wave excitation spectrum in La2CuO4. The values of the in-plane exchange…
We report on temperature dependent measurements of the Longitudinal Spin Seebeck Effect (LSSE) in the mixed valent manganite La$_{0.7}$Ca$_{0.3}$MnO$_3$. By disentangling the contribution arising due to the Anisotropic Nernst effect, we…
We use the double exchange (DE) model via degenerate orbitals and tight-binding approximation to study the magnetoconductivity of a canted A-phase of pseudo-cubic manganites. It is argued that the model is applicable in a broad…
Motivated by recent discovery of colossal magnetoresistance in La$_(1-x)$Ca$x$MnO$_3$ and other manganites, we have studied the double exchange model. We argue that the forced alignment of conduction-electron spin with the core spins that…