相关论文: Critical dynamics of a uniaxial and dipolar ferrom…
We resolve a longstanding puzzle for the static and dynamic critical behavior of Gadolinium by a combined theoretical and experimental investigation. It is shown that the spin dynamics of a three dimensional ferromagnet with hcp lattice…
We review our current understanding of the critical dynamics of magnets above and below the transition temperature with focus on the effects due to the dipole--dipole interaction present in all real magnets. Significant progress in our…
A theory is proposed for kinetic effects in isotropic Heisenberg antiferromagnets at temperatures above the Neel point. A metod based on the analysis of a set of Feynman diagrams for the kinetic coefficients is developed for studying the…
Thermally driven transitions between ferromagnetic and paramagnetic phases are characterized by critical behavior with divergent susceptibilities, long-range correlations, and spin dynamics that can span kHz to GHz scales as the material…
We investigate the static critical behaviour of a uniaxial magnetic layer, with finite thickness L in one direction, yet infinitely extended in the remaining d dimensions. The magnetic dipole-dipole interaction is taken into account. We…
We report a neutron spin-echo study of the critical dynamics in the $S=5/2$ antiferromagnets MnF$_2$ and Rb$_2$MnF$_4$ with three-dimensional (3D) and two-dimensional (2D) spin systems, respectively, in zero external field. Both compounds…
The dynamic phase transitions have been studied, within a mean-field approach, in the kinetic spin-1 Ising model Hamiltonian with arbitrary bilinear and biquadratic pair interactions in the presence of a time varying (sinusoidal) magnetic…
We study systems of classical magnetic dipoles on simple cubic lattices with dipolar and antiferromagnetic exchange interactions. By analysis and Monte Carlo (MC) simulations, we find how the antiferromagnetic phases vary with uniaxial and…
Green function diagrammatic technique is used to investigate a model ferromagnet in the case, when the effective spin at a site is compounded of two anisotropically interacting electron spins. The results are: the transverse magnetic…
The influence of uniaxial anisotropy and the dipole interaction on the direction of the magnetization of ultra-thin ferromagnetic films in the ground-state is studied. The ground-state energy can be expressed in terms of anisotropy…
The spin dynamics of the semiclassical Heisenberg model with uniaxial anisotropy, on the layered triangular lattice with antiferromagnetic coupling for both intralayer nearest neighbor interaction and interlayer interaction is studied both…
The bivariate high-temperature expansion of the spin-spin correlation-function of the three-dimensional classical XY (planar rotator) model, with spatially-anisotropic nearest-neighbor couplings, is extended from the 10th through the 21st…
We numerically investigate the non-equilibrium critical dynamics in three-dimensional anisotropic antiferromagnets in the presence of an external magnetic field. The phase diagram of this system exhibits two critical lines that meet at a…
We consider quantum Heisenberg ferro- and antiferromagnets on the square lattice with exchange anisotropy of easy-plane or easy-axis type. The thermodynamics and the critical behaviour of the models are studied by the pure-quantum…
It is found that subtle changes in the external magnetic field and temperature result in dramatic changes in the ultrafast response of spins to a femtosecond laser excitation in a ferrimagnetic Gd/FeCo multilayer. A total of six distinct…
Three dimensional anisotropic XY ferromagnet driven by elliptically polarized propagating magnetic field wave has been extensively investigated by Monte Carlo simulation with Metropolis single spin flip algorithm. Both the effects of the…
We investigate spin-$\frac{1}{2}$ anisotropic model of a linear chain of triangles with competing ferro- and antiferromagnetic interactions and ferromagneic Heisenberg interactions between triangles. For a certain ratio between interactions…
The static transverse and longitudinal correlation functions (CF) of a 3-dimensional ferromagnet are calculated for the exactly solvable anisotropic spherical model (ASM) determined as the limit D \to \infty of the classical D-component…
We explore critical properties of two-dimensional lattices of spins interacting via an anisotropic Heisenberg Hamiltonian and subject to incoherent spin flips. We determine the steady-state solution of the master equation for the density…
The magnetic properties of a system of three interacting magnetic elliptical discs are examined. For the various levels of uniaxial anisotropy investigated a complicated series of phase transitions exist. These are marked by the critical…