伊特和稀土铁的高温导热性
Makoto Tachibana1, Cédric Bourgès2,3, Takao Mori1,4
1Research Center for Materials Nanoarchitechtonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan.
Journal of physics. Condensed matter : an Institute of Physics journal
|September 22, 2025
概括
测量了稀土铁石榴石中的导热率. 伊特铁石榴石遵循音声模型,而磁性稀土石榴石由于音声相互作用而显示较低的导电性.
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
- 固态化学 固态化学
背景情况:
- 和稀土铁石 (R3Fe5O12) 是铁磁绝缘体,在磁性和自旋应用中具有显著的潜力.
- 了解它们的热特性对于优化设备性能和探索新应用至关重要.
研究的目的:
- 为了研究单晶R3Fe5O12 (R = Y,Gd,Dy,Yb) 在300773 K的温度范围内的导热率 (κ).
- 阐明磁性稀土离子及其对热传输机制的相互作用的影响.
主要方法:
- 使用已确定的技术,实验测量导热率.
- 分析与音声模型和磁性特性相关的热传输行为.
主要成果:
- 对于伊铁石 (Y3Fe5O12),热导率高达其基里温度 (TC ≈ 555 K) 是通过纯音声模型很好地描述的.
- 结合磁性稀土离子的铁石榴石具有降低的导热性.
- 双铁石榴石 (Dy3Fe5O12) 显示了最低的导热值.
结论:
- Y3Fe5O12的导热率主要由声子主导,在TC以下的磁子贡献微不足道.
- 磁性稀土离子的存在显著影响热导率,主要是通过声子和晶体场激发之间的强相互作用.
- Dy3Fe5O12的低导热性归因于明显的声子-晶体场相互作用,突出了稀土元素在石榴石热管理中的作用.
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