在全内全外磁绝缘体中的移动金属域壁
Eric Yue Ma1, Yong-Tao Cui2, Kentaro Ueda3
1Geballe Laboratory for Advanced Materials (GLAM), Stanford University, Stanford, CA, USA. Department of Applied Physics, Stanford University, Stanford, CA, USA.
概括
研究人员在磁绝缘体Nd2Ir2O7中发现了高度导电的磁域壁. 这些域壁表现出独立于温度的抗性和独特的特性,挑战了以前关于磁绝缘体的理论.
科学领域:
- 凝聚物质物理学
- 材料科学
- 固态物理
背景情况:
- 磁域墙是不同顺序的磁域之间的接口.
- 在磁绝缘器中,由于磁性秩序受到干扰,预计域壁具有不同的电特性.
- 之前的理论假设磁绝缘体内的域壁具有显著的电行为变化.
研究的目的:
- 在磁绝缘体Nd2Ir2O7中研究磁域壁的电特性.
- 通过实验确定该特定材料中的域壁是否表现出异常导电性.
- 在不同温度和磁场下描述这些域壁的行为.
主要方法:
- 运输测量用于探测电气特性.
- 用空间分辨率的微波阻抗显微镜绘制纳米级电导率.
- 实验是在Nd2Ir2O7上进行的,这是一种具有全进全出磁性的材料.
主要成果:
- 在Nd2Ir2O7中发现了高导电磁域壁.
- 这些域壁具有每平方约1千克的板电阻,基本上独立于温度.
- 域壁表现出平滑的形态,缺乏障碍的固定,并显示出与全进全出磁顺序一致的响应.
结论:
- 在Nd2Ir2O7中发现高导电域壁挑战了现有的磁绝缘体模型.
- 这些发现表明域壁可以是导电通道,与此前的预期相反.
- 这些域壁的独特特性为探索磁性材料中的奇特电子现象提供了新的途径.
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