随机场远程Ising模型的一维阶段排序动态
Ramgopal Agrawal1,2, Federico Corberi3, Eugenio Lippiello4
1School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067, India.
Physical review. E
|November 18, 2023
概括
远程相互作用在短时间内加速随机场Ising模型 (RFIM) 中的域增长. 然而,由于相互竞争的力量,它们出乎意料地减缓了长期对数体系中的动态.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 统计力学 统计力学
- 复杂的系统复杂的系统.
背景情况:
- 一维随机场Ising模型 (RFIM) 描述了具有竞争性铁磁相互作用和灭混乱的系统.
- 在RFIM中的阶段排序动态通常以域增长和粗化为特征.
- 最近邻互动导致域增长中的特定缩放行为.
研究的目的:
- 调查远程 (LR) 相互作用对1D RFIM相序动态的影响.
- 了解LR相互作用如何修改特征域增长和粗化过程.
- 分析LR相互作用诱导的驱动力和随机场固定力之间的竞争.
主要方法:
- 理论分析1DRFIM的铁磁合分解为r^{-(1+σ)}.
- 在不同LR相互作用强度 (σ) 下检查域大小演变R(t).
- 研究磁化场的空间相关性和自相关性函数.
主要成果:
- LR相互作用改变了从R(t) ∼t^{1/2}到R(t) ∼t,然后是R(t) ∼t^{1/(1+σ) 的预交会生长.
- 非对称的对数增长R ((t) ∼ ((lnt) ^{α(σ)}被修改为α (((σ) <2,表示较慢的动态.
- 空间相关性显示所有 σ 的超普遍性;自相关性显示 σ<1.1 的超普遍性.
结论:
- LR相互作用加速短期域增长,但减缓1D RFIM中的非对称动态.
- 随机场固定和LR驱动力之间的平衡控制了观察到的动态.
- 相关函数的超普遍性取决于LR相互作用的范围.
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