在多晶体Tb0.7Sr0.3MnO3化合物中,结构扭曲驱动的极子传输和表状磁热性质
Kalipada Das1, Dipak Mazumdar2, I Das3
1Department of Physics, Seth Anandram Jaipuria College, 10 Raja Naba Krishna Street, Kolkata-700005, West Bengal, India.
Physical chemistry chemical physics : PCCP
|December 2, 2024
概括
这项研究表明,磁场显著改变了Tb$_{0.7}$Sr$_{0.3}$MnO$_{3}$的特性. 由于其独特的磁变化和低场磁阻,该材料具有用于爱立信制冷的潜力.
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:
- 多晶体Tb$_{0.7}$Sr$_{0.3}$MnO$_{3}$因其复杂的磁性和运输行为而受到研究.
- 了解晶体结构,磁场和电子特性之间的相互作用对于新型材料应用至关重要.
研究的目的:
- 综合分析Tb$_{0.7}$Sr$_{0.3}$MnO$_{3}$的结构性,磁性,磁传输性和磁热性属性.
- 探索磁场强度对材料基本状态和传输机制的影响.
- 为了评估这种化合物的潜力,用于冷应用,如爱立信制冷.
主要方法:
- 结构,磁,电电阻和磁热效应的实验性表征.
- 对温度依赖的磁变化和磁电阻的分析.
- 使用小极子跳跃和可变范围跳跃模型对电阻的建模.
主要成果:
- 随着磁场强度的增加,观察到基本状态的显著修改.
- 发现强烈的晶体学扭曲控制了磁性和磁性传输特性.
- 确定了明显的"桌式"磁变化和60K左右的显著低电场磁阻.
- 电阻数据被极子传输机制解释得很好,表明一个非adiabatic极子跳跃与大电子-声波合.
结论:
- Tb$_{0.7}$Sr$_{0.3}$MnO$_{3}$在磁场下表现出可调节的特性,由结构扭曲驱动.
- 该材料的磁热效应和磁电阻表明了磁性制冷技术的潜力.
- 该研究提供了对3d-4f交换相互作用及其在观察到的现象中的作用的见解.
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