混合磁声声局部化增强了近铁状玻璃状状态的功能
Michael E Manley1, Paul J Stonaha1, Nickolaus M Bruno2,3
1Materials Sciences and Technology Division, Oak Ridge National Lab, Oak Ridge, TN 37831, USA.
Science advances
|June 14, 2024
概括
在Heusler合金桥中局部化了磁声和晶格振动的磁声-声声混合模式,增强了近铁玻璃状态的功能. 这一发现提供了关于玻璃性如何提高冷却应用的材料性能的见解.
科学领域:
- 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:
- 靠近铁玻璃状态的铁材料由于相互竞争的相关性而显示出增强的功能性.
- 这些增强的基础物理仍然不太清楚.
- Ni45Co5Mn36.6In13.4 豪斯勒合金表现出磁场诱导的形状记忆和磁热效应,这与多电热冷却有关.
研究的目的:
- 为了研究铁性材料在铁性玻璃形成的边缘附近增强功能背后的物理.
- 了解竞争相关性在Ni-Co-Mn-In海斯勒合金等材料中的作用.
主要方法:
- 使用中子散射来研究Ni45Co5Mn36.6In13.4海斯勒合金.
- 分析的重点是识别和描述磁声声互动及其空间分布.
主要成果:
- 确定了局部化的磁声声声混合模式,将声声声声和磁性刺激 (magnons) 联系起来.
- 这些混合模式导致了磁场诱导的声音频率的显著变化.
- 由于这些模式,热量反应增加了三倍,相位稳定性发生了变化.
- 这些模式归因于声子和磁子通过与磁域相结合的反相边界的局部化.
结论:
- 局部化的磁声声声混合模式是近铁状玻璃状物质中观察到的增强功能的关键.
- 这些模式为磁场控制格子振动和材料特性提供了一种机制.
- 这些发现提供了关于玻璃性如何提高具有竞争相关性的材料的功能性的一般见解.
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