在纳秒时间尺度上对抗铁磁状态的非挥发性电气控制
S Ghara1, M Winkler1, S W Schmid1,2
1University of Augsburg, Experimental Physics V, Center for Electronic Correlations and Magnetism, Institute of Physics, 86159 Augsburg, Germany.
Physical review letters
|October 5, 2025
概括
研究人员在低于尼尔温度的氧化物 (Co_{3}O_{4}) 中展示了对抗铁磁 (AFM) 状态的电压脉冲控制. 这一突破使先进的自旋电子设备能够实现超快速,非易失性切换.
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
- 这就是Spintronics.
背景情况:
- 对抗铁磁 (AFM) 状态的电学操纵对于AFM自旋电子非常重要,但面临着重大挑战.
- 需要新的材料平台来有效控制AFM状态.
研究的目的:
- 用绝缘材料中的电压脉冲来证明对AFM状态的完全控制.
- 为了研究在Co_{3}O_{4}中磁电效应及其对尼尔向量方向的依赖.
- 探索Co_{3}O_{4}作为超高速自旋电子器件平台的潜力.
主要方法:
- 使用电压脉冲对AFM状态进行电气操纵,以隔离Co_{3}O_{4}低于其尼尔温度.
- 研究了线性磁电效应及其与尼尔向量方向的关系.
- 应用电场和磁场的组合来操纵尼尔向量,实现平稳的旋转和突然的反转.
主要成果:
- 通过使用电压脉冲,在Co_{3}O_{4}中实现了对AFM状态的完全控制.
- 证明强烈的线性磁电效应受尼尔向量方向的支配.
- 展示了由于磁电能和磁晶异质性之间的相互作用而在需求时操纵尼尔向量的能力.
- 在几十纳秒内的宏观体积中,在时间逆转的AFM状态之间实现了非挥发性切换.
结论:
- Co_{3}O_{4}表现出强烈的线性磁电效应,允许对AFM状态进行电压控制的操纵.
- 像Co_{3}O_{4}这样的半立方反铁磁体是对AFM领域超快操纵的理想平台.
- 这些发现为开发具有快速切换能力的先进AFM旋转器件铺平了道路.
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