在异质接口上由无形层诱导的phonon动态行为
Quanjie Wang1, Jie Zhang2, Yucheng Xiong3
1Institute of Micro/Nano Electromechanical System and Integrated Circuit, College of Mechanical Engineering, State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, Shanghai 201620, China. xjliu@dhu.edu.cn.
Physical chemistry chemical physics : PCCP
|February 26, 2024
概括
无形介层通过改变声子行为来阻碍异构结构中的热传输. 化使这些层重新结晶,在改进的热纳米设备中,可显著增加高达38%的热导电量.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 纳米技术纳米技术
背景情况:
- 在异构结构接口上的无形间层是由于材料不匹配而产生的.
- 了解它们对界面热传输的影响对于热纳米设备至关重要.
研究的目的:
- 在无形间层中研究声子传输的微观机制.
- 分析无形层厚度和特性对热传导的作用.
主要方法:
- 在GaN/AlN接口上进行声波包模拟.
- 音声传输和反射的每模式分析.
- 化技术来修改接口形态.
主要成果:
- 无形层定位声子,并通过调整极化来阻碍它们的传输.
- 运输阻力随着无形层厚度 (L) 的增加而增加.
- 高频横声学 (TA) 声子由于极化转换和散射,具有很高的传导性.
- 观察到多个声子反射和干扰效应.
- 化重新结晶了无形层,将界面热导率提高了高达38% (对于L = 3nm).
结论:
- 无形间层显著阻碍了声子传输.
- 通过回火的接口工程可以显著提高热导电性.
- 这些发现对于设计高效的热纳米设备至关重要.
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