在BaFe2中的磁性记忆效应 (As0.68P0.32)
Alina M Badea Ionescu1, Ion Ivan1, Corneliu F Miclea1
1National Institute of Materials Physics, 405A Atomistilor Str., 077125 Magurele, Romania.
Materials (Basel, Switzerland)
|November 9, 2024
概括
研究人员在铁基超导体中发现了与结构转变相关的磁性记忆效应. 这种效应影响了的动态,超出了通常的第二磁化峰值 (SMP).
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
- 超导电性 超导电性 超导电性
背景情况:
- 同等替代的BaFe2 ((As1-xPx) 2是一种基于铁的超导体.
- 这种材料在临界电流密度与磁场之间呈现第二磁化峰值 (SMP).
- 临界电流密度与温度的不同寻常的峰值效应被观察到在米到正方形 (RST) 结构过渡附近.
研究的目的:
- 为了研究形到正方形 (RST) 结构过渡对BaFe2中的旋流动力学的影响2.
- 探索与结构转变相关的磁性记忆效应.
- 了解结构过渡和刺激之间的关系.
主要方法:
- 进行了多波交流灵敏度测量.
- 实验是在三个冷却模式下进行的:场冷却,零场冷却和带有变暖的场冷却.
- 在不同的交流频率上测量了交流灵敏度,以探测时间尺度上的差异.
主要成果:
- 在特定的温度区域发现了明显的磁性记忆效应,这归因于结构转变的方向.
- 在低AC频率和高AC频率下,第三波灵敏度的显著差异表明结构转换和旋激发的时间表不同.
- RST结构过渡对动态的影响远远超出了第二次磁化峰值 (SMP) 的开始.
结论:
- 形到正方形 (RST) 的结构转变显著影响铁基超导体的动力学.
- 确定了与结构转变方向相关的磁性记忆效应.
- 这些发现揭示了结构变化和旋行为之间的复杂相互作用,影响了超导特性.
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