在旋转-3/2中磁交换相互作用和非Debye放松挫败了卡戈梅磁体Co3V2O8
H Singh1, M Skoulatos2, D C Joshi1
1Department of Physics, Indian Institute of Technology, Guwahati 781039, Assam, India.
概括
铁磁卡戈梅格子系统Co3V2O8的磁交换参数被实验确定为2.88 ± 0.02 K. 这项研究还确定了材料内的多个磁相过渡和旋转翻转过渡.
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:
- 卡戈梅晶格是一个具有独特属性的几何挫折磁系统.
- 了解磁交换相互作用对于设计新型磁性材料至关重要.
研究的目的:
- 为了实验性地确定Spin-3/2铁磁Kagomé格子系统的磁交换参数 (J/kB),Co3V2O8.8.
- 为了研究Co3V2O8.8.中的磁性相位转换和旋转转换.
- 分析电荷载体传输机制和介电性质.
主要方法:
- 使用海森伯格线性链模型的直流磁感性 (χ(T)) 的温度依赖性.
- 热容量 (C-T) 和差异性同热磁化曲线的分析.
- 对复杂的模量和阻抗光谱进行Kohlrausch-Williams-Watts分析.
- 电阻分析和频率依赖的交流电导率 (σac(ω)) 测量.
主要成果:
- 发现磁交换参数J/kB为2.88 ± 0.02 K,与理论预测一致.
- 确定了五种不同的磁相过渡 (6.2-11.2 K) 和旋转转过渡 (7.7-9.6 kOe),并将它们映射到HT平面上.
- 临界指数α被确定为0.18 ± 0.01 (T
- 观察到非德拜型双极松和Mott变频波段跳跃的电荷载体.
- 两个不同的激活能量 (0.37 eV和2.29 eV) 被确定为电荷传输.
结论:
- 实验结果证实了在Co3V2O8.8中存在着主要的近邻铁磁交换合.
- 该研究提供了对复杂的磁相图和Co3V2O8.8的运输特性的全面了解.
- Co3V2O8表现出有趣的介电松和电荷传输机制,这与潜在的应用有关.
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