It is pointed out that the low-temperature form of the surface correction depends only on the curvature of the bulk spin-wave dispersion relation near k=0, provided the exchange interactions between the spins are short-ranged in a sense described in the text. The phase transition of a semi-infinite Heisenberg ferromagnet having easy-axis (perpendicular) anisotropy of the form -Ds(Sz)2 (Ds>0) in the surface and easy-plane anisotropy of the form -Db(Sz)2 (Db. In this paper, the variation of the intrinsic domain magnetization It is. Being able to image coherent spin-wave transport is crucial for developing interference-based spin-wave devices. On a obtenu le spectre des excitations des ondes de spin de surface et on les a comparé avec celui des ondes de spin de volume. The damping rate Γqis calculated using the leading diagrams due to the quartic-order deviations from the harmonic spin Hamiltonian. To read the full-text of this research, you can request a copy directly from the author. A survey is presented of a continued fraction representation for the Green functions in the mixed local-Bloch basis for the spin operators, related to the transfer-matrix formalism, which allows explicit evaluation of the diagonal Green function at each layer. To determine the dispersion equation, the method Our approach is a moment-conserving decoupling procedure for suitable defined Green functions. However, the penetration depth of these waves is almost the same as for the Heisenberg model. are explained in the memory function analysis as due to either spinwave A theoretical investigation has been made of surface spin waves localized at a (001) surface of a ferromagnetic simple cubic lattice with nearest and next-nearest neighbor exchange interactions. In Appendix A are lists of some 260 distinct and useful bcc lattices of 9 to 32 vertices. of the spinwave peaks whose number and positions depend on the system size and We examine theoretically the influence of surface anisotropy on the magnetization of the Heisenberg ferromagnet in its outermost layers. magnetization of the S = 1/2XY ferromagnet have been computed on these bcc lattices in the lowest states for S in a Two-Dimensional Non-Heisenberg Ferromagnet, The SpinWave Contribution to the Heat Capacity of Ferromagnetic Thin Films, Theory of the surface magnetization profile and the low-energy, spin-polarized, inelastic electron scattering off insulating ferromagnets at finite T, Green's function theory of the spin-1 low-dimensional quantum XY ferromagnet, Effects of surface exchange anisotropy in Heisenberg ferromagnetic insulators, Surface Corrections to the Specific Heat of Ferromagnetic Films, Self-consistent Thomas-Fermi calculation of potential and current distributions in a two-dimensional Hall bar geometry, Exact diagonalization of the S = 1/2 XY ferromagnet on finite bcc lattices to estimate T = 0 properties on the infinite lattice, Some thermodynamic properties of a semi-infinite Heisenberg ferromagnet, Field Dependence of the Intrinsic Domain Magnetization of a Ferromagnet, Optimized mean-field theory for the three-dimensional XY spin model, Influence of surface anisotropy on the magnetization of the Heisenberg ferromagnet, Magnetization direction of a semi-infinite Heisenberg ferromagnet with perpendicular surface anisotropy, Low-temperature static and dynamic behavior of the layered classical XY ferromagnet, Temperature-dependent band structure of a ferromagnetic semiconductor film. finite-sized systems, there are multiple sequences of weak peaks on both sides Dust acoustic solitary structures in multidust fluids superthermal plasma, We present the linear spin wave theory calculation of the superfluid phase of a hard-core boson, Nous présentons des calculs théoriques en théorie des ondes de spin linéaire de la phase superfluide du modèle. The temperature of the phase transition is determined. of transformation matrix is used. centre-ville, Montréal, QC H3C 3J7, Canada. We have included also a magnetic anisotropy in each monolayer. Of the various one-dimensional quantum spin systems the XY model is no doubt the simplest model … The numerical calculations on the base of the equations obtained yield a good agreement with experimental data on the layered perovskites La2CuO4, K2NiF4 and Rb2NiF4, and the Monte Carlo results for the anisotropic classical systems. Results for an fcc lattice with a (111) surface turn out qualitatively similar to previous results for a sc lattice with a (100) surface. If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Our theoretical analysis is based on a Green’s-function method. The resulting four-dimensional integrals are the functional dependence is as the inverse square root of the field. The interface interaction is assumed to be ferromagnetic. The layer-sublattice magnetization, the internal energy, and the specific heat in Heisenberg ferrimagnetic three-layer superlattices and two-dimensional three-layer systems are calculated by employing retarded Green's functions within the framework of the linear spin-wave approximation. The effects of a surface on the contribution to the low temperature specific heat of a Heisenberg ferromagnet from the magnetic degrees of freedom and on the spin deviation associated with a given site are computed by a Green's function method. The excitations spectrum for the surface spin waves has been obtained and compared with that for bulk spin waves. 05.50.+q Lattice theory and statistics (Ising, Potts, etc.) The effects of the exchange constants, the spin values, and the temperature on the internal energy and the specific heat of the two systems are investigated systematically. The curves show resonances near one or both ends of the bulk magnon energy band, depending on the surface exchange parameters. The layer-sublattice magnetization, the internal energy, and the specific heat in Heisenberg feffi-magnetic three-layer superlattices and two-dimensional three-layer systems are calculated by employing retarded Green's functions within the framework of the linear spin-wave approximation.

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