Influence of Dipole Interaction on the Phase Transitions Due to Temperature Variation in Two-Dimensional Ferromagnets

Abstract

We investigate the influence of dipole interaction on the phase transitions due to temperature variation in two-dimensional ferromagnets. The spectra of quasi-particles at the points of the phase transitions from "the easy-axis phase" to "the angular phase" and from "the easy-plane phase" to "the angular phase" are obtained. The temperatures of the phase transitions are found. The numerical evaluation of the temperature interval of angular phase existence is in good agreement with experimental data.

Dynamic and static properties of rigidly fixed ultrathin ferromagnetic films with S = 1 and competing anisotropies

“…(23), (24), (28), and (29)) and the quadrupole phase (Eqs. (40) and (41)) and depends on the relationship among the single-ion anisotropy constants, as well as on the orientation of the wave vector.…”

“…It is known that in 2D systems, long-range magnetic ordering is stabilized by magnetic dipole and/or magnetoelastic interactions. 19,22,23 The inclusion of magnetic dipole interactions can lead to a spatially inhomogeneous distribution of the magnetization in a sample, i.e., to the appearance of a spatially inhomogeneous state-a domain structure. [24][25][26][27][28] The systems described above have been studied fairly well for the case of small single-ion anisotropy constants.…”

Phase diagram of Fe1−Co ultrathin film

“…Several models have been developed to describe such phase transitions. One of these models assumes a competition between the singleion anisotropy and the magnetic dipole interaction [7,8], while other models are based on the temperature dependence of the single-ion anisotropy and the influence of some other relativistic interactions [9,10].…”

Temperature dependence of the spectra of elementary excitations for anisotropic S = 1 ferromagnetics

“…There have been many studies of this sort based on various approaches. [25][26][27][28][29][30][31][32][33][34][35] Thus, unusual magnetism that does not fit the simple phenomenological approach with its assumption of a constant magnetization length continues to be of research interest. [33][34][35] However, as far as we know the 1063-777X/2014/40(11)/6/$32.00 V C 2014 AIP Publishing LLC 972 dynamic effects of quantum spin reduction at finite temperatures have not been discussed previously.…”