热传输在一个维护角动量的网格中
1Department of Physics, Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices, and Key Laboratory of Quantum State Construction and Manipulation (Ministry of Education), Renmin University of China, Beijing 100872, People's Republic of China.
Physical review. E
|April 18, 2024
概括
在非线性网格中,超扩散是惊人的强大,即使添加横向运动. 热传输因变化的声子无平均值路径而增强,扩展了普遍性发现.
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
- 非线性动力学是一种非线性动力学.
背景情况:
- 一维非线性网格由于Lévy分布式热模式而表现出异常的热扩散.
- 超扩散和异常导热的特点是功率定律在时间和系统大小上的分歧.
- 以前的模型考虑了能量,动量和拉伸等保存量.
研究的目的:
- 为了研究二维横向运动对非线性网格中的热扩散的影响.
- 在这样的系统中探索总角动量的保存和扩散特性.
- 确定异常热传输的普遍性是否在额外的保存量和运动中持续存在.
主要方法:
- 一个一维的非线性格子模型的理论分析.
- 包括二维横向运动和分析角度运动量保存的分析.
- 检查能量扩散传播器和热传输特性.
主要成果:
- 热模式仍然遵循莱维分布,保持超扩散 (β>1).
- 异常导热 (大小依赖导电性,α>0) 保持不变.
- 守恒角动量的扩散是弹道的.
- 热传输强度显著增强,这是由于修改了声无平均值路径.
结论:
- 在非线性网格中异常热传输的普遍性扩展到具有横向运动和角运动量保存的系统.
- 尽管扩散指数没有变化,但增强的热传输突出显示了晶格动态和热特性之间的复杂相互作用.
- 这些发现表明,基于莱维的扩散模型在复杂的物理系统中具有更广泛的适用性.
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