一项复杂的磁性研究:证据表明,在远程磁性排序下,旋转玻璃过渡存在,并且与声子模式的重新规范化相关
Sipun Mohanty1, Samrat Mukherjee1
1Department of Physics, National Institute of Technology Patna, Bihar 800005, India.
概括
我们报告了Nd2CoIrO6和Sm2CoIrO6双矿的复杂磁性行为,这是由于相互作用的磁性离子. 这些材料表现出铁磁排序和旋转玻璃行为,在低温下观察到格子磁性合.
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:
- 具有多个磁性离子的双重矿提供复杂的磁现象.
- 了解3d,5d和4f磁子网的相互作用对于新型磁性材料至关重要.
研究的目的:
- 为了合成和表征Nd2CoIrO6和Sm2CoIrO6双矿.
- 研究由 Nd/Sm,Co 和 Ir 磁子网的相互作用产生的复杂磁性行为.
- 探索磁性排序和格子动态之间的关系.
主要方法:
- 固态合成方法用于样品制备.
- 用X射线衍射进行结构分析.
- 用X射线光电子光谱测定氧化状态.
- 对磁过渡的磁感应度测量 (dc和ac).
- 温度依赖的拉曼光谱法用于声子模式分析.
主要成果:
- Nd2CoIrO6和Sm2CoIrO6都结晶成一个单临结构 (P21/n).
- 证实了Ir (Ir4+和Ir5+) 的多个氧化状态.
- 参磁-铁磁过渡在100 K左右被观察到,归因于CO2+和Ir4+反平行对齐.
- 在 Nd2CoIrO6 中,与 Vogel-Fulcher 动态,在订单温度以下确定了类似旋转玻璃的行为.
- 声波模式显示在铁磁过渡下方与磁性顺序的合.
结论:
- 合成的双矿表现出由3d-5d-4f亚晶格相互作用驱动的复杂磁性排序.
- 集群旋转玻璃的行为与这些材料中的铁磁性共存.
- 磁压力效应,或格子磁性合,影响在低温下声子的行为.
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