在轻微Gd-Doped酸 CaMnO3中的Kondo类行为
Tomislav Ivek1, Matija Čulo1, Nikolina Novosel1
1Institut za fiziku, Bijenička cesta 46, HR-10000 Zagreb, Croatia.
Nanomaterials (Basel, Switzerland)
|June 11, 2025
概括
这项研究研究了氧化物,Ca1-xGdxMnO3,揭示了具有电阻上升和负磁阻的金属行为. 结果表明,铁磁金属区域在反铁磁矩阵中的Kondo-like散射和透.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学是一种材料科学.
- 固态化学 固态化学
背景情况:
- 氧化物 () 呈现复杂的相图,具有具有竞争性的铁磁 (FM) 金属和反铁磁 (AFM) 绝缘状态.
- 巨大的磁阻是矿的标志性特征,但导电性机制仍在争论中.
- 了解这些机制对于材料科学和凝聚物质物理学至关重要.
研究的目的:
- 研究未经充分探索的Ca1-xGdxMnO3矿中的导电机制.
- 分析与磁体结构相关的磁传输特性.
- 阐明磁相与电传输之间的相互作用.
主要方法:
- 在烧结的纳米晶体Ca1-xGdxMnO3样本 (x=0.05,0.10) 上进行了磁传输测量.
- 测量范围包括从2K到300K的温度和高达16T的磁场.
- 分析的重点是电阻和磁阻行为.
主要成果:
- 这两种化合物在低温下都表现出金属的行为,其特点是电阻率上升.
- 观察到一个显著的负磁电阻.
- 观察到的现象与Kondo-like散射和透效应一致.
结论:
- 该研究提供了关于Ca1-xGdxMnO3.3中复杂导电机制的见解.
- 作为关键因素,建议将Kondo类散射在Gd杂质上和FM金属区域的透作为关键因素.
- 这些发现有助于对矿物理学的基本理解.
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