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arXiv · 1001.0372

A generalised Landau-Lifshitz equation for isotropic SU(3) magnet

Julia Bernatska·Petro Holod
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Abstract

In the paper we obtain equations for large-scale fluctuations of the mean field (the field of magnetization and quadrupole moments) in a magnetic system realized by a square (cubic) lattice of atoms with spin s >= 1 at each site. We use the generalized Heisenberg Hamiltonian with biquadratic exchange as a quantum model. A quantum thermodynamical averaging gives classical effective models, which are interpreted as Hamiltonian systems on coadjoint orbits of Lie group SU(3).

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Julia Bernatska, Petro Holod. 2014-09-18. A generalised Landau-Lifshitz equation for isotropic SU(3) magnet. https://doi.org/10.1088/1751-8113%2F42%2F7%2F075401

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