Ground-state structures of a two-dimensional (2D) system composed of superparamagnetic charged particles are investigated by means of molecular dynamics simulation. The charged particles trapped in a quadratic potential interact with each other via the repulsive, attractive, and magnetic dipole-dipole forces. Simulations are performed within two regimes: a one-component system and a two-component system where the charged particles have the identical charge-to-mass ratio. The effects of magnetic dipole-dipole interaction, mixing ratio of the two species and confinement frequency on the ground-state structures are discussed. It is found that as the strength of the magnetic dipole increases, the charged particles tend to self-organize into chainlike structures. The two species particles exhibit different structural features, depending on the competition of electrostatic repulsive interaction, magnetic dipole-dipole interaction and confinement force. The potential lanes are observed through analyzing the global potential of the magnetic particles, which guide the unmagnetic particles aligning themselves in the direction of the potential lanes.

中文翻译：

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二次阱中二维超顺磁系统的结构

通过分子动力学模拟研究了由超顺磁性带电粒子组成的二维（2D）系统的基态结构。捕获在二次电势中的带电粒子通过排斥，吸引和磁偶极子-偶极力相互作用。模拟在两种情况下执行：一组分系统和二组分系统，其中带电粒子具有相同的电荷质量比。讨论了磁偶极-偶极相互作用，两种物质的混合比以及约束频率对基态结构的影响。发现随着磁偶极子强度的增加，带电粒子趋于自组织成链状结构。这两种物质具有不同的结构特征，取决于静电排斥相互作用，磁偶极-偶极相互作用和约束力的竞争。通过分析磁性粒子的整体电势可以观察到电势线，这将引导非磁性粒子在电势线方向上对齐。