The field of spin electronics (spintronics) was initiated by the discovery of giant magnetoresistance (GMR) for which Fert[1] and Grunberg[2] were awarded the 2007 Nobel Prize for Physics. GMR arises from differential scattering of the majority and minority spin electrons by a ferromagnet (FM) so that the resistance when the FM layers separated by non-magnetic (NM) spacers are aligned by an applied field is different to when they are antiparallel. In 1996 Slonczewski[3] and Berger[4] predicted that a large spin-polarised current could transfer spin-angular momentum and so exert a spin transfer torque (STT) sufficient to switch thin FM layers between stable magnetisation states[5] and, for even higher current densities, drive continuous precession which emits microwaves[6]. Thus, while GMR is a purely passive phenomenon which ultimately depends on the intrinsic band structure of the FM, STT adds an active element to spintronics by which the direction of the magnetisation may be manipulated. Here we show that highly non-equilibrium spin injection can modify the scattering asymmetry and, by extension, the intrinsic magnetism of a FM. This phenomenon is completely different to STT and provides a third ingredient which should further expand the range of opportunities for the application of spintronics.
A strain-controlled magnetostrictive pseudo spin valve
通过逆磁致伸缩效应实现磁场控制是提高基于巨磁电阻效应的高能效存储和传感器件性能的有效途径。本文报道了在铁电PMN-PT衬底上生长的Co $/$ Cu $/$ Py赝自旋阀的横向电场驱动的应变介导磁性能调制。结果表明,随着电场的增加,赝自旋阀的巨磁电阻率逐渐减小,这是由于应变诱导磁弹性各向异性的贡献导致Co层的磁化强度偏离了初始方向.此外,我们表明,应变诱导的磁各向异性有效地转移磁致伸缩Co层的开关场,同时保持开关场的近零磁致伸缩Py层不受影响,由于其可忽略的磁致伸缩常数。我们认为,磁致伸缩优化的磁性薄膜在适当的工程多层结构可以提供一条路径,以提高自旋电子器件中的选择性磁开关。
Anomalous Transverse Response and Multi-Field Ferrialtermagnetic-Ferroelectric Valve with CrSb Flakes
Huazhong University of Science and Technology(华中科技大学);Beijing Institute of Technology(北京理工大学);Chongqing University of Posts and Telecommunications(重庆邮电大学)
研究提出铁磁反铁磁体概念,以 CrSb 薄片实现,集成铁电体和 Cu 间隔层设计出铁磁反铁磁-铁电阀,该阀有高自旋过滤率等特性,确立了铁磁反铁磁体在多场控制等自旋电子学和电子学方面的丰富平台地位。
Interplay between structure and magnetism in $Mo_{12} S_9 I_9$ nanowires
我们用从头算密度泛函方法研究了Mo $_{12}$ S $_{9}$ I $_{9}$纳米线的平衡几何构型和电子结构.这些异常稳定的纳米线的骨架由刚性的官能化Mo八面体组成,通过柔性的双稳态硫桥连接。这种结构灵活性转化为几乎没有能源成本的情况下拉伸高达约20%的能力。纳米线从导体转变为窄隙磁性半导体,其结构异构体之一。
Comparison of dynamical and equilibrium surface spin-reorientations: Inferences on the nature of the phase transitions in the presence of dipole interactions
在铁磁薄膜的自旋重取向转变过程中,长程偶极相互作用对二维磁性的影响已被广泛研究。尽管有大量关于通过偶极相互作用稳定的垂直畴相的实验信息,但到畴相或从畴相的转变很微妙,很难通过实验表征。磁化率测量显示,在自旋重取向转变附近没有发散作为厚度的函数-一个零的结果,很难解释的信心。本文报道了Fe/2 ML Ni/W(110)薄膜在生长过程中的磁化率测量结果,并分别给出了该薄膜的动力学和平衡态的再取向转变。动态版本发生时,增加的膜厚度导致域壁depin,和系统从一个配置,最大限度地减少局部能量的一个,最大限度地减少全局能量。动态转变\textit{is}标记的发散磁化率测量与沿面内W[001]方向施加的字段。两个版本的相同的自旋重取向过渡艾滋病的实验表征偶极相互作用的相变的影响的比较研究。这种比较证实了原来的零结果发现在磁化率测量的平衡过渡,尽管它的名字,自旋重取向转变在铁磁薄膜中没有临界相变在磁化或其方向。
From Ultrafast Demagnetization to Ultrafast Spintronics : a 30 years story
Université de Lorraine(洛林大学);CNRS, Institut Jean Lamour(法国国家科学研究中心,让·拉穆尔研究所);Department of Physics, Freie Universität Berlin(柏林自由大学物理系);Center for Science and Innovation in Spintronics, Tohoku University(东北大学自旋电子学科学与创新中心)
Orbital angular momentum in crystalline solids: non-equilibrium theory
Max-Born-Institute for Non-Linear Optics(马克斯·玻恩非线性光学研究所);Institute for Theoretical Solid-State Physics, Freie Universität Berlin(柏林自由大学理论凝聚态物理研究所);Scientific Computing Department, Science and Technology Facilities Council UK Research and Innovation (STFC-UKRI), Rutherford Appleton Laboratory(英国研究与创新科学技术设施委员会(STFC-UKRI)拉瑟福德阿普尔顿实验室科学计算部)
Non-volatile Orbital magnetoelectric effect in a two-dimensional electron gas
CNR-SPIN(意大利国家研究委员会自旋物理研究所);Univ. Grenoble Alpes(格勒诺布尔阿尔卑斯大学);CEA(法国原子能和替代能源委员会);CNRS(法国国家科学研究中心);Grenoble-INP(格勒诺布尔国立理工学院);SPINTEC(自旋电子学与自旋器件实验室);Laboratoire Albert Fert(阿尔伯特·费特实验室);Thales(泰雷兹集团);Université Paris-Saclay(巴黎萨克雷大学);Photon Science Division, Paul Scherrer Institut(保罗谢尔研究所光子科学部);Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS)(斯特拉斯堡材料物理与化学研究所);Université de Strasbourg(斯特拉斯堡大学);Department of Applied Physics, Indian Institute of Information Technology Vadodara(瓦多德拉印度信息技术学院应用物理系);Dipartimento di Fisica, Università di Cagliari(卡利亚里大学物理系);CNR-IOM(意大利国家研究委员会无机材料与光化学研究所);Dipartimento di Fisica “E. R. Caianiello,” Universitá di Salerno(萨莱诺大学E.R.凯亚涅洛物理系);Faculty of Environmental Life, Natural Science and Technology, Okayama University(冈山大学环境生命自然科学与技术学部)