在发展格里菲斯阶段中Co/Mn相互作用的作用,在La2CoMnO6中减少粒子大小
Suvayan Saha1, Sanjib Banik2, Apurba Dutta3
1CMP Division, Saha Institute of Nuclear Physics, 1/AF, Bidhannagar, Kolkata 700 064, India.
ACS applied materials & interfaces
|March 24, 2025
概括
纳米晶体La2CoMnO6由于颗粒大小减少而过渡到格里菲斯相 (GP),与散装材料不同. 这种转变是由铁磁集群间相互作用和纳米材料中减少的抗位体障碍驱动的.
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
- 磁力学 磁力学 是一种
背景情况:
- 双矿La2CoMnO6正在研究其磁性特性.
- 了解非格里菲斯阶段 (NGP) 和格里菲斯阶段 (GP) 之间的过渡对于先进材料至关重要.
- 粒子大小显著影响材料中的磁相转换.
研究的目的:
- 为了全面研究从NGP到GP在La2CoMnO6中的过渡,随着粒子大小的减少.
- 阐明集群间相互作用和抗位障碍在这个阶段过渡中的作用.
- 为了比较大量和纳米晶体La2CoMnO6的磁性行为.
主要方法:
- 大量和纳米晶体La2CoMnO6的合成.
- 详细的磁化和运输研究.
- 磁相互作用和障碍的理论分析.
主要成果:
- 大量La2CoMnO6表现出两个铁磁 (FM) 过渡 (在~155K和~85K) 和NGP.
- 纳米晶体La2CoMnO6显示了一个单一的FM过渡 (在220K) 和展示GP.
- 在所有系统中,在基里温度以上存在短距离FM相互作用.
- 抗铁磁性集群相互作用和抗位障碍 (ASD) 在批量限制GP形成.
- 纳米材料中的铁磁交集相互作用,减少的ASD和表面效应促进了GP的出现.
结论:
- 在La2CoMnO6中的颗粒大小的减少推动了从NGP到GP的过渡.
- 集群间相互作用和ASD是管理NGP-GP过渡的关键因素.
- 纳米结构材料提供了一种途径,通过受控合成和表面效应来调整磁相.
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