在热稳定的吸附位点上的单原子磁铁:Dy在NaCl上(100)
M Pivetta1, M Blanco-Rey2,3,4, S Reynaud1
1Ecole Polytechnique Fédérale de Lausanne (EPFL), Institute of Physics, CH-1015 Lausanne, Switzerland.
Physical review letters
|March 13, 2026
概括
单个Dysprosium原子在NaCl(100) 薄膜上表现出磁性双稳定性. 这些原子在热稳定的表面上起到第一个单原子磁铁的作用,为新的磁性存储技术铺平了道路.
科学领域:
- 固态物理 固态物理
- 材料科学 材料科学 材料科学
- 量子磁力 量子磁力 量子磁力
背景情况:
- 单原子磁铁 (SAM) 对于下一代数据存储至关重要.
- 开发具有高热稳定性和长旋转寿命的SAM是一个关键的挑战.
- (Dy) 是一个有前途的元素,可以在原子尺度上产生磁性.
研究的目的:
- 为了研究在NaCl100) 薄膜上被吸附的单个Dysprosium原子的磁性.
- 为了确定使用NaCl作为稳定的单原子磁铁的基质的可行性.
- 探索吸附点对Dy原子磁性行为的影响.
主要方法:
- NaCl ((100) 薄膜的表轴生长.
- 单个原子的沉积到NaCl表面.
- 使用对原子结构和磁性特性敏感的技术进行表征 (例如扫描道显微镜,磁性测量).
- 分析电子配置 (4f占用) 和磁放松时间 (T1).
主要成果:
- 在NaCl上替换Na的单个Dy原子显示了高达300K的热稳定性.
- 这些Dy原子表现出平面外磁化和2.5K时10秒的旋转放松时间 (T1).
- 在Cl和桥位上被吸附的Dy原子显示不同的电子配置 (4f10) 和磁性歇斯底里.
- 观察到Dy在顶部Cl位的长磁放松时间 (T1 = 550s在0.3T和2.5K) .
结论:
- NaCl100) 作为实现稳定的单原子磁铁的有效平台.
- 在NaCl上的二原子表现出有希望的磁性双稳定性和长的旋转放松时间.
- 这些发现为设计强大的原子级磁器件打开了道路.
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