磁极子可以达到十万个玻尔磁极子
Pavel A Usachev1, Vladimir N Kats1, Leonid A Shelukhin1
1Ioffe Institute, St. Petersburg, 194021, Russia. pavlov@mail.ioffe.ru.
Materials horizons
|November 4, 2024
概括
研究人员在铁磁半导体欧氧化物 (EuO) 中光学产生了巨大的磁极子. 这些准粒子表现出创纪录的磁时刻,使潜在的光学控制对固体中的磁状态.
科学领域:
- 光磁主义是指光磁主义.
- 固态物理 固态物理
- 材料科学是一种材料科学.
背景情况:
- 控制与光的基本相互作用是光磁学和电子学的关键.
- 磁极子是用于外部刺激操纵的潜在准粒子.
- 需要支持具有较大的磁矩的光诱导磁极子的材料来控制磁场.
研究的目的:
- 为了展示磁极子的光学生成与巨大的净磁时刻.
- 调查欧氧化物 (EuO) 作为这种现象的材料的潜力.
- 探索对固体中的磁态进行高效的光学控制.
主要方法:
- 在EuO电影中利用光诱导的法拉第效应.
- 采用了双色探针技术.
- 研究了产生磁极子的皮秒时间动力学.
主要成果:
- 在EuO中实现了磁极子的光学生成,其磁矩超过了10万个波尔磁子.
- 证明,当光子暴露超过带隙时,巨大的磁极子在库里温度以上形成.
- 在旋转分裂的5d导电带中观察到放松动态.
结论:
- EuO支持光学生成的磁极子,具有前所未有的磁矩.
- 这一发现为磁态的高效光学控制提供了一个平台.
- 突出了铁磁半导体在光磁应用中的潜力.
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