The new types of nonlinear localized state of generalized order parameter in the three-layered structure of band antiferromagnets with congruent sections of the Fermi surface are obtained. The nonlinear effects inside the narrow plane defects between the layers representing the local magnetization in the direction of polarization of the spin density wave are described by the nonlinear source function. The variation of the Ginsburg–Landau functional near the Lifshitz point leads to nonlinear Schrödinger equation (NSE) with cubic nonlinear terms and self-consistent nonlinear potential modeling the plane defects. The dispersion equations of two type stationary nonlinear localized states are derived. The solutions of dispersion equations in explicit analytical form in dependence on characteristics of plane defects and the distance between them are found and analyzed. The localized states of order parameter existing only near the plane defects with nonlinear response are obtained.

中文翻译：

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多层磁结构中广义阶参数局部化的新特征

获得了具有费米面全等截面的能带反铁磁体三层结构中广义阶参数的新型非线性局域态。代表自旋密度波极化方向的局部磁化的层之间的窄平面缺陷内部的非线性效应由非线性源函数描述。Lifshitz 点附近 Ginsburg-Landau 泛函的变化导致非线性薛定谔方程 (NSE) 具有三次非线性项和自洽非线性势对平面缺陷进行建模。推导了两类稳态非线性局域态的色散方程。找到并分析了依赖于平面缺陷特征和它们之间距离的显式解析形式的色散方程的解。获得了仅存在于具有非线性响应的平面缺陷附近的有序参数的局部状态。