磁流体的相位分离:非对称状态和非平衡动力学
Anuj Kumar Singh1, Varsha Banerjee1
1Department of Physics, Indian Institute of Technology Delhi, New Delhi 110016, India.
Physical review. E
|January 20, 2024
概括
使用斯托克迈耶模型模拟了磁粒子自我组装. 该研究揭示了密度依赖的生长机制和独特的磁性排序,导致具有多样化应用的坚固结构.
科学领域:
- 软物质物理学 软物质物理学
- 材料科学 材料科学 材料科学
- 计算化学计算化学
背景情况:
- 磁粒子的合悬浮体表现出复杂的自我组装行为.
- 斯托克迈尔 (SM) 模型描述了磁粒子与伦纳德-斯和双极-双极相互作用,显示了气-液相共存.
- 了解不平衡动态对于控制自组装至关重要.
研究的目的:
- 通过分子动力学模拟,研究合物悬浮中的磁性颗粒的自我组装动力学.
- 描述斯托克迈尔模型在非平衡演变期间的空间和磁性排序.
- 为了确定密度依赖的粗化机制和由此产生的形态.
主要方法:
- 斯托克迈耶 (SM) 模型的综合分子动力学模拟.
- 将系统从高温同质阶段灭到共存区域.
- 分析密度依赖生长规律 (扩散和水力动力学) 和顺序参数动力学.
主要成果:
- 通过扩散 (t^{1/3}) 和惯性 (t^{2/3}) 增长规律观察到密度依赖的粗化.
- 在不平衡演化过程中确定了空间和磁性秩序的发展.
- 描述了不对称的形态,包括球体,气泡,圆柱体和板块,具有类似于雅努斯的磁性.
- 发现了在旋转模式内磁性秩序增长的意想不到的非保存动态.
结论:
- 磁粒子的自我组装由密度依赖的粗化控制,并表现出明显的空间和磁性排序.
- 由此产生的坚固且不易挥发的结构具有独特的磁性和多样化的潜在应用.
- 该研究提供了对磁流体自组装及其技术影响的基本见解.
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