在强烈相关的抗铁磁CrN中,磁应力驱动的金属绝缘体过渡
Bidesh Biswas1,2, Sourav Rudra1,2, Rahul Singh Rawat1,2
1Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560064, India.
Physical review letters
|October 6, 2023
概括
研究人员发现了一种新的方法来控制金属绝缘体过渡,使用化中的磁应力. 压缩应变使室温转换成为可能,为新型电子设备打开了大门.
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
- 量子材料是一种量子材料.
背景情况:
- 金属绝缘器相位过渡通常由库伦排斥或皮尔尔斯不稳定性驱动.
- 磁应力是理论上提出的,但在实验上未经验证的,在具有强烈自旋格子合的材料中这些过渡的驱动因素.
研究的目的:
- 通过实验证明和理解磁应力驱动的金属绝缘体过渡的机制.
- 调查应变和材料组成在化中这种过渡过程中的作用.
主要方法:
- 实验性表征包括结构性,磁性和电子传输测量.
- 第一原则理论建模分析旋转,电荷和格子自由度的相互作用.
主要成果:
- 证实了化 (CrN) 中磁应力驱动的金属绝缘体过渡的存在.
- 建立了过渡温度和应变控制的无极形磁应力之间的直接比例.
- 证明压力应变会诱导室温转变,而拉力应变和非磁性补充剂会减少它.
结论:
- 磁应力代表了相关材料中金属-绝缘体相变的新型物理起源.
- 这些发现统一了旋转,电荷和格子相互作用,为理解这些现象建立了新的范式.
- 这项工作为设计具有可调节相位过渡特性的新型电子设备铺平了道路.
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