Related papers: Role of temperature-dependent spin model parameter…
Thermodynamic flunctuations in BaFe2As2 is addressed with a first-principles formulation of the Helmholtz energy by accounting for the mixture of various electronic states each distinguished by different spin orientation distributions. We…
We study analytically and numerically a couple of paradigmatic spin models, each described in terms of two sets of variables attached to two different thermal baths with characteristic timescales $T$ and $\tau$ and inverse temperatures $B$…
The thermodynamic properties (magnetization, magnetic susceptibility, transverse and longitudinal correlation lengths, specific heat) of one- and two-dimensional ferromagnets with arbitrary spin S in a magnetic field are investigated by a…
Optically induced demagnetization of 3d metallic ferromagnets proceeds as fast as ~100 fs and is a crucial prerequisite for spintronic applications, such as ultrafast magnetization switching and spin transport. On the 100 fs time scale, the…
A stochastic differential equation that describes the dynamics of single-domain magnetic particles at any temperature is derived using a classical formalism. The deterministic terms recover existing theory and the stochastic process takes…
We examine the temperature dependence of the electronic states in the stripe phase of high-Tc cuprates by using the t-J model with a potential that stabilizes vertical charge stripes. Charge and spin-correlation functions and optical…
We study the fluctuations of the spin per site around the thermodynamic magnetization in the mean-field Blume-Capel model. Our main theorem generalizes the main result in a previous paper (Ellis, Machta, and Otto) in which the first…
In the paper a study of a model magnetoelastic solid system is presented. The system of interest is a mean-field magnet with nearest-neighbour ferromagnetic interactions and the underlying s.c. crystalline lattice with the long-range Morse…
A one dimensional kinetic Ising model at a finite temperature on a semi-infinite lattice with time varying boundary spins is considered. Exact expressions for the expectation values of the spin at each site are obtained, in terms of the…
Temperature-dependent magnetic properties of Nd$_2$Fe$_{14}$B permanent magnets, i.e., saturation magnetization $M_\text{s}(T)$, effective magnetic anisotropy constants $K_i^\text{eff}(T)$ ($i=1,2,3$), domain wall width $\delta_w(T)$, and…
A model of magnetic interactions in the ordered ferromagnetic FePt is proposed on the basis of first-principles calculations of non-collinear magnetic configurations and shown to be capable of explaining recent measurements of magnetic…
Experiments on the temperature and time dependence of the response function and the field cooled magnetisation of a Cu(Mn) spin glass at temperatures below the zero field spin glass temperature are used to explore the non-equilibrium nature…
We provide a macroscopic theory and experimental results for magnetic resonances of antiferromagnetically-coupled ferrimagnets. Our theory, which interpolates the dynamics of antiferromagnets and ferromagnets smoothly, can describe…
Magnetization manipulation is becoming an indispensable tool for both basic and applied research. Theory predicts two types of ultrafast demagnetization dynamics classified as type I and type II. In type II materials, a second slower…
We study computational behavior of a mesoscopic model describing temperature/external magnetic field-driven evolution of magnetization. Due to nonconvex anisotropy energy describing magnetic properties of a body, magnetization can develop…
Thermodynamic properties of cubic Heisenberg ferromagnets with competing exchange interactions are considered near the frustration point where the coefficient $D$ in the spin-wave spectrum $E_{\mathbf{k}}\sim D k^{2}$ vanishes. Within the…
Optical and magneto-optical properties of magnetic materials have been widely exploited to characterize magnetic structures and phenomena, however, their temperature dependence is not well understood. This study implements the supercell…
The Hubbard model on fcc-type lattices is studied in the dynamical mean-field theory of infinite spatial dimensions. At intermediate interaction strength finite temperature Quantum Monte Carlo calculations yield a second order phase…
The origins of the anomalous temperature dependence of magnetocrystalline anisotropy in (Fe$_{1-x}$Co$_{x}$)$_{2}$B alloys are elucidated using first-principles calculations within the disordered local moment model. Excellent agreement with…
With use of homogeneous model for magnetic sub-lattice of compound La1-x CaxMnO3 allowing for Heisenberg superexchange and double exchange between nearest neighbors the temperature dependence of spontaneous magnetization on a separate site…