We consider a system of nonlinear differential equations describing the antiferromagnetism victor in ferrite film. The contains two parameters and admits family exact solutions with plane phase trajectories. Perturbation such leads to Hill equation periodic coefficient. study stability equilibrium state equation.

A model unifying superconductivity and antiferromagnetism using an underlying approximate SO(5) symmetry has injected energy into the field of high-temperature superconductivity. This model might lead to a variety of interesting solitons. In this paper, the idea that superconducting vortices may have antiferromagnetic cores is presented, along with the results of some preliminary numerical work...

We show that the motion of a single hole in the infinite-U Hubbard model with frustrated hopping leads to weak metallic antiferromagnetism of kinetic origin. An intimate relationship is demonstrated between the simplest versions of this problem in one and two dimensions, and two of the most subtle many body problems, namely, the Heisenberg Bethe ring in one dimension and the two-dimensional tri...

The discovery of superconductivity in LaFeAsO1−xFx has stimulated substantial interest in iron-based high-temperature superconductors (Fe-HTSs). Until now, several Fe-HTSs were discovered. They can be divided into two classes. The first class is iron pnictide materials.1−3 They contain two-dimensional FePn (Pn = pnictogens) tetrahedron layers and atomic sheets (e.g., Ba, K) or complex blocks [e...

We here present a fixed agents version of an original model of the emergence of hierarchies among social agents first introduced by Bonabeau et al. Having interactions occurring on a social network rather than among ’walkers’ doesn’t drastically alter the dynamics. But it makes social structures more stable and give a clearer picture of the social organisation in a ‘mixed’ regime.

The renormalization group approach to correlated fermions is used to determine the phase diagram of the oxide cuprates modeled by the t − t′ Hubbard model at the Van Hove filling. Spin–dependent interactions give rise to instabilities corresponding to ferromagnetic, antiferromagnetic and d-wave superconducting phases. Antiferromagnetism and d-wave superconductivity arise from the same interacti...

A local, second-order (truncated) approximation is applied to the Hubbard model in three dimensions. Lowering the temperature, at half-filling, the paramagnetic ground state becomes unstable towards the formation of a commensurate spin-density-wave (SDW) state (antiferromagnetism) and sufficiently far away from half-filling towards the formation of incommensurate SDW states. The incommensurate-...

The renormalization group approach to correlated fermions is used to determine the phase diagram of the oxide cuprates modeled by the t ? t 0 Hubbard model at the Van Hove lling. Spin{dependent interactions give rise to instabilities corresponding to ferromagnetic, antiferromagnetic and d-wave superconducting phases. Antiferromagnetism and d-wave superconductivity arise from the same interactio...