超快的低温金属绝缘体接口在Pt/Gd3Fe5O12异构结构中的声子动力学和热传输
Deepankar Sri Gyan1, Ni Li1, Zhantao Chen
1Department of Materials Science and Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
Structural dynamics (Melville, N.Y.)
|November 28, 2025
概括
这项研究揭示了金属绝缘体接口的声学和热传输的不同声波动态. 检测到高达740 GHz的声波,显示热传输的低声波传输.
科学领域:
- 量子科学和技术 量子科学和技术
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
背景情况:
- 接口热和声学现象在量子科学和自旋电子设备中至关重要.
- 了解这些现象需要同时测量热和声特性.
- 金属/绝缘体异构结构是探索这些界面效应的关键平台.
研究的目的:
- 为了研究在金属/绝缘体接口上的声音和热传输的独特动态.
- 使用超快速技术探测接口的声学和热性质.
- 为了确定声学减噪,声子平均自由路径,以及Pt层中的格鲁尼森无声性.
主要方法:
- 在GdGG基板上制造Pt/GdIG异构结构.
- 时间解析的超快X射线衍射,以追踪Pt层中的结构动态.
- 五秒钟的光脉冲激发产生宽带声脉冲.
- 波段分析用于检测高达740 GHz的声波振荡.
- 博尔兹曼运输方程建模用于导热分析.
主要成果:
- 在声波和热传输的特征性声波频率范围内观察到不同的动态.
- 产生宽带声脉冲,在Pt/GdIG接口部分反射.
- 检测到高达740 GHz的声学振荡,揭示了Pt.中的声学抑制和声平均自由路径.
- 格鲁尼森是Pt层确定的一种harmonicity参数.
- 在热传输频率下,相比于亚特拉赫兹声学,发现声波传输在热传输频率下低.
结论:
- 这项研究强调了金属绝缘体接口上的声子传输的频率依赖性.
- 用于热传输的低声波传输对设备性能有重大影响.
- 这些发现为设计先进的自旋电子和量子设备提供了关键的见解.
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