论文标题
在二维铁磁超流体中的深色孤子状磁性域壁
Dark soliton-like magnetic domain walls in a two-dimensional ferromagnetic superfluid
论文作者
论文摘要
我们报告了均匀铁磁自旋-1冷凝物中稳定的磁性域壁，其特征是磁化强度具有深色的孤子曲线，具有不变的超流体密度。我们找到了具有和没有磁场的相互作用参数的特定比率的精确固定溶液，并开发出适用于整个铁磁相的精确分析溶液。在没有磁场的情况下，该域壁通过$ \ textrm {so}（3）$旋转旋转将二进制冷凝物中的各种独特的孤立激发联系起来，否则这些旋转是没有连接的。值得注意的是，研究了准二维（准2D）系统的动力学，我们表明，域壁的站立波激发无衰减，对蛇的不稳定性保持稳定。域壁在动态上不稳定，导致磁化强度垂直生长的模式在离开域壁不变时垂直生长。在存在白噪声的情况下，实时动力学表明，这种“自旋扭曲”不稳定性不会破坏磁性域壁的拓扑结构。
We report a stable magnetic domain wall in a uniform ferromagnetic spin-1 condensate, characterized by the magnetization having a dark soliton profile with nonvanishing superfluid density. We find exact stationary solutions for a particular ratio of interaction parameters with and without magnetic fields, and develop an accurate analytic solution applicable to the whole ferromagnetic phase. In the absence of magnetic fields, this domain wall relates various distinct solitary excitations in binary condensates through $\textrm{SO}(3)$ spin rotations, which otherwise are unconnected. Remarkably, studying the dynamics of a quasi-two-dimensional (quasi-2D) system we show that standing wave excitations of the domain wall oscillate without decay, being stable against the snake instability. The domain wall is dynamically unstable to modes that cause the magnetization to grow perpendicularly while leaving the domain wall unchanged. Real time dynamics in the presence of white noise reveals that this "spin twist" instability does not destroy the topological structure of the magnetic domain wall.
