来自Ising系统中自旋极化极子的巨大磁阻力
Ying-Fei Li1,2,3, Emily M Been1,2,3, Sudhaman Balguri4
1Stanford Institute for Materials and Energy Sciences, Stanford Linear Accelerator Center (SLAC) National Accelerator Laboratory, Menlo Park, CA 94025.
概括
在EuMX材料中,巨大的磁阻 (CMR) 是由纠的磁性和晶格相互作用引起的,而不是传统的机制. 这种新奇的行为与旋转极化极子在铁磁星团边界散射有关.
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:
- 巨大的磁阻 (CMR) 通常涉及Kondo-Ruderman-Kittel-Kasuya-Yosida (Kondo-共振散射) 交叉,磁过渡或拓变化.
- 一个新的材料类别,EuMX (M = Cd,In,Zn;X = P,As),表现出与既有现象不同的新型CMR.
研究的目的:
- 调查EuMX材料家族中的巨大磁阻 (CMR) 的起源.
- 通过实验和理论方法探索EuCd2P2的基本机制.
主要方法:
- 角度分辨率光辐射光谱学 (ARPES) 探测电子结构.
- 密度函数理论 (DFT) 计算用于理论见解.
- 系统地调查材料和温度的依赖性.
主要成果:
- 低能光谱重量与在最大磁阻温度附近的电阻异常相关.
- 观察到的光谱是不连贯的,缺乏兰道准粒子.
- 非准粒子的行为归因于通过Eu-Eu混合的纠的磁性和晶格相互作用.
- CMR起源被确定为铁磁星团边界的自旋极化极子的散射.
结论:
- 在EuMX家族显示一个独特的CMR机制,由合作互动驱动.
- 纠的磁性和晶格相互作用是观察到的非准粒子电子状态的关键.
- 研究结果提供了这些材料中强烈的相关性和拓学的见解,并说明了凝聚物质中复杂的新兴现象.
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