相关论文: PM-FM transition in a DE model
The experimental studies of the paramagnetic-antiferromagnetic phase transition through M\"{o}ssbauer spectroscopy and measurements of temperature and field dependencies of magnetic susceptibility in the layered Cu$_{0.15}$Fe$_{0.85}$PS$_3$…
In the paper a possibility of metallic ferromagnetic state realization in a generalized Hubbard model with more complete accounting of electron-electron interactions, in particular, the correlated hopping and exchange interaction integrals…
We study the momentum- and temperature dependencies of magnetic susceptibilities and magnetic exchange in paramagnetic fcc iron by a combination of density functional theory and supercell dynamical mean-field theory (DFT+DMFT). We find that…
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 study the shift of the the superconducting transition temperature $T_c$ in ferromagnetic-superconducting bi-layers and in a superconducting film supplied a square array of ferromagnetic dots. We find that the transition temperature in…
Considering a general situation where a semiconductor is doped by magnetic impurities leading to a carrier-induced ferromagnetic exchange coupling between the impurity moments, we show theoretically the possible generic existence of three…
The prospects of half-metallic ferromagnetism being induced by the incorporation of C atoms into alkaline-earth-metal-oxides are investigated by the first principle calculation. The origin of the ferromagnetism is discussed through the…
The double-exchange model, which has been extensively studied in the context of colossal magneto-resistance in perovskite manganese oxides, is known to exhibit a ferromagnetic metallic state at low temperatures because of the interplay…
The macroscopic magnetizations of a RuSr2(Eu0.7Ce0.3)2Cu2O10+d sample were investigated. A ferromagnet-like transition occurs around T_M in the low-field magnetization. Highly nonlinear M(H), non-Curie-Weiss susceptibility, and slow…
We employ dynamical mean-field theory to identify the materials properties that optimize Tc for a generalized double-exchange (DE) model. We reach the surprising conclusion that Tc achieves a maximum when the band angular momentum j equals…
Magnetic state is a partial ordered state if only part of the electrons in the system give contribution to the magnetic order. We study Heisenberg model of two sublattice spin system, on the body-centered cubic lattice, with…
In a previous work a model was proposed for the phase transitions of crystals with localized magnetic moments which at low temperature have a "conical" arrangement that at higher T transforms into a more symmetrical structure (depending on…
We use the Kondo lattice model to investigate the possibility of ferromagnetism and half-metallicity in local moment systems. Using the spectral density approach and making use of the fact that the spontaneous magnetization of local moment…
In this work we rederive the Lamb-Retherford energy shift for an atomic electron in the presence of a thermal radiation. Using the Dalibard, Dupont-Roc and Cohen-Tannoudji (DDC) formalism, where physical observables are expressed as…
The thermal-history dependence of the magnetoelastic transition in (Mn,Fe)2(P,Si) compounds has been investigated using high-resolution neutron diffraction. As-prepared samples display a large difference in paramagnetic-ferromagnetic…
We present general expressions for the magnetic transition rates in beam Electron Paramagnetic Resonance (EPR) experiments of anisotropic spin systems in the solid state. The expressions apply to general spin centers and arbitrary…
The off-diagonal disorder caused by random spin orientations in the paramagnetic (PM) state of the double exchange (DE) model is described by using the coherent-potential-approximation (CPA), which is combined with the variational…
The resistivity around the ferromagnetic transition temperature in the double exchange model is studied by the Schwinger boson approach. The spatial spin correlation responsible for scattering of conduction electrons are taken into account…
Solid atomic hydrogen is one of the simplest systems to undergo a metal-insulator transition. Near the transition, the electronic degrees of freedom become strongly correlated and their description provides a difficult challenge for…
We present theoretical description of conduction electrons interacting with a domain wall in ferromagnetic metals. The description takes into account interaction between electrons. Within the semiclassical approximation we calculate the…