Equatorial non-equilibrium states in magnetization dynamics of ferromagnets: Generalization of Suhl’s spin-wave instabilities
نویسندگان
چکیده
We investigate the nonlinear dynamics underlying the evolution of a 2-D ferromagnetic film with uniaxial anisotropy and an oscillating magnetic field. Considering the associated Landau-Lifshitz spin evolution equation with Gilbert damping included, we study the dynamics in terms of the stereographic variable. We identify several new fixed points for suitable choice of external field. In particular, we analyze fixed points of the spin vector in the plane transverse to the anisotropy axis, and study their stability under homogeneous and spin wave perturbations. We further obtain a generalized Suhl’s instability criterion, giving the condition for exponential growth of P-modes under spin wave perturbations.
منابع مشابه
Equatorial and related non-equilibrium states in magnetization dynamics of ferromagnets: Generalization of Suhl’s spin-wave instabilities
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