通过平均场方法了解异性磁体中的多元论效应
Yulia Klunnikova1, Alex Y Karpenkov1, Benedikt Beckmann1
1Institute of Materials Science, Technical University of Darmstadt, Darmstadt, Germany.
Science and technology of advanced materials
|July 2, 2025
概括
这项研究探讨了磁性材料中的多重效应,详细说明了磁场和机械旋转如何影响变化. 研究人员量化了交叉合效应,证实了总的多重效应是个别效应减去合贡献的总和.
科学领域:
- 热力学是一种热力学.
- 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:
- 具有磁性异质的材料表现出受磁场 (H) 和机械旋转 (τ) 影响的热力学变化.
- 多热效应 (MCE) 涉及由常规磁热和旋转贡献产生的变化.
- 了解这些合效应对于开发先进的磁冷却技术至关重要.
研究的目的:
- 为了研究具有磁性异性质的材料中的多元化效应.
- 为了分离和量化磁场和机械旋转对总变化的贡献.
- 确定和验证分子场模型中的交叉合系数.
主要方法:
- 利用分子场模型分析热力学状态变化.
- 将总变化 (ΔST) 分开为传统的磁热量 (ΔSm) 和旋转 (ΔSφ) 组件.
- 计算的交叉合多元度系数 (χτ,H 和 χH,τ) 对于异性磁性材料.
主要成果:
- 成功分离了传统和旋转MCE贡献.
- 确定满足基本热力学同一性的交叉合系数.
- 确认了总的多元论效应可以用单个效应的和减去一个合项来表示: ΔST = ΔST,τ(H) + ΔST,H(θ) - ΔScoupling.
结论:
- 分子场模型有效地分离了无极性磁性材料中的多极性效应贡献.
- 交叉合效应起着重要作用,必须在计算总变化时加以考虑.
- 这项工作为理解和优化多元理论材料的潜在应用提供了一个框架.
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