Influence of magnetoelastic coupling on the phase transitions in two-dimensional non-Heisenberg magnetics with biquadratic interaction

Normal modes and possibility of spatially inhomogeneous phases for a 2D ferromagnet with biquadratic and magnetoelastic interactions

“…The gaps in the quasimagnon spectra (14) coincide in the absence of the magnetodipolar interaction 0), which corresponds to the results of Ref. [36].…”

Phase transitions in a ferromagnet with an anisotropic biquadratic exchange interaction

“…For example, unlike non-Heisenberg magnets with isotropic exchange, 21,22,25,29 in which the soft mode is a quasielastic branch of excitations, in the given case phase the transitions occur via the quasimagnon branch. Taking the magnetoelastic interaction into account leads to a static renormalization of the energy gap in the spectrum of quasimagnon excitations.…”

“…21 phase transition but also a change of the phase to which the transition of the system from the FM phase occurs ͑the QP 2 phase instead of QP 1 ͒.…”

“…21, then sin 2 = 0. This leads to a different form of the eigenfunctions of the one-site Hamiltonian, and hence, to a different relation of the spin operators to the Hubbard operators, etc.…”