Alternating superlattice textures in driven nanomagnets
In this present paper, alternating superlattice textures in nanomagnets driven by spin-transfer torques are studied. The authors deal with two states, superhexagons and square-like patterns. They show that the alternating superhexagons emerge through a homoclinic bifurcation. The emergence of dynamical patterns by means of low-dimensional bifurcations is explained. A reduced representation of the superhexagon in terms of a Galerkin expansion is obtained. The authors show that the spin-transfer torque is the dominant dissipation mechanism of alternating superlattices. Then, an oscillatory square-like state that emerges through an Andronov-Hopf instability is investigated. The authors plot the temporal evolution of the average magnetization, magnetic energy, and average resistance for some given values. In an appendix, the authors explain the Galerkin expansion of the magnetization equations.
scientific article; zbMATH DE number 7257344
scientific article