在域增长问题中的光谱能量转移
Pradeep Kumar Yadav1, Mahendra Kumar Verma2, Sanjay Puri1
1School of Physical Sciences, <a href="https://ror.org/0567v8t28">Jawaharlal Nehru University</a>, New Delhi-110067, India.
Physical review. E
|November 20, 2024
概括
域增长模型,如Cahn-Hilliard和时间依赖的Ginzburg-Landau,显示了小结构如何消失. 频谱能量转移在保存和非保存动态之间存在差异,影响系统如何达到统一状态.
科学领域:
- 物理 物理学 物理
- 材料科学 材料科学 材料科学
- 计算科学 计算科学
背景情况:
- 域增长是一个基本的过程,其中小结构消失,留下较大的结构.
- 了解这一过程在各种科学领域至关重要,包括材料科学和统计物理学.
- 光谱能量转移在这些系统的动态中起着关键作用.
研究的目的:
- 在两个标准域增长模型中研究光谱能量转移.
- 为了比较Cahn-Hilliard (CH) 方程的动态与保存的动态,以及时间依赖的Ginzburg-Landau (TDGL) 方程与非保存的动态.
- 分析非线性术语如何促进富里埃模式之间的能量转移.
主要方法:
- 对光谱能量转移的分析.
- 卡恩-希利亚德 (CH) 方程的数值模拟.
- 时间依赖的金兹堡-兰道方程 (TDGL) 的数值模拟.
主要成果:
- 两个方程中的非线性项消散波动,并驱动富里埃模式之间的能量转移.
- 在TDGL方程中,只有零波向量模式 (k=0) 存活下来,从而导致均状态.
- 由于其保存的动力学,CH方程对k=0模式表现出不同的行为,突出了不同的动力学.
结论:
- 卡恩-希利亚德方程和TDGL方程在它们的域增长过程中表现出根本不同的动态.
- 保存定律显著影响这些模型中的长期行为和光谱能量转移.
- 该研究提供了对物理系统中模式形成和粗化的机制的洞察.
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