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零力矩半金属:它如何改变自旋电子学?

The zero-moment half metal: How can it change spintronics?
课程网址: http://videolectures.net/kolokviji_coey_zero_moment/  
主讲教师: J. M. D. Coey
开课单位: 都柏林圣三一大学
开课时间: 2016-01-25
课程语种: 英语
中文简介:
零矩半金属是一种铁磁金属,在费米能级上,自旋上升或自旋下降的电子的态密度有一个间隙。这样的材料,如果化学计量,应该有一个自旋矩,它是每个公式单元,4, 3, 2,1,或0的Bohr magnetons的整数。零力矩的情况特别有趣。这种材料是磁有序的,没有净力矩(像反铁磁体),但与反铁磁体不同,磁子晶格是不等价的,在费米能级上有100%的自旋极化。它不会产生杂散场,对外场不敏感。尽管de Groot在25年前预测,但第一次实验实现的数据是Mn2Ru0。5Ga(MRG)是最近才出版的。首先介绍这种立方Heusler合金薄膜的制备和性能,然后讨论其对垂直磁隧道结、磁记忆和超高频自旋力矩振荡器的潜在影响。对于最后一个应用,有可能创造出能够突破太赫兹差距的片上自旋电子振荡器,并确保下一代大数据革命的未来。
课程简介: A zero-moment half metal is a ferromagnetic metal with a gap in the density of states at the Fermi level for either the spin-up or spin-down electrons. Such a material, if stoichiometric, should have a spin moment which is an integral number of Bohr magnetons per formula unit, 4, 3, 2, 1, or 0. The zero-moment case is particularly intriguing. The material will be magnetically ordered with no net moment (like an antiferromagnet) but unlike an antiferromagnet the magnetic sublattices are inequivalent, and there is 100% spin polarization at the Fermi level. It creates no stray field, and is insensitive to external field. Although predicted by de Groot 25 years ago, data on the first experimental realization, Mn2Ru0.5Ga (MRG), was only published recently. The preparation and properties of thin films of this cubic Heusler alloy will first be presented, and then its potential impact on perpendicular magnetic tunnel junctions, magnetic memory and ultra-high-frequency spin torque oscillators will be discussed. For the last application, there is a prospect of creating on-chip spintronic oscillators that can breach the THz gap, and assure the future of the big data revolution for the next generation.
关 键 词: 零矩半金属; 铁磁金属; 自旋电子振荡器
课程来源: 视频讲座网
数据采集: 2022-03-28:zkj
最后编审: 2024-01-22:liyy
阅读次数: 36