我们观察到高效的动态自旋注入Y $_3$ Fe $_5$ O $_{12}$(YIG)到NiO,反铁磁(AF)绝缘体,通过强耦合,和强大的自旋传播NiO高达100 nm的厚度介导的AF自旋相关性。引人注目的是,在YIG和Pt之间插入薄NiO层显著增强了驱动到Pt中的自旋电流,这表明在YIG/NiO和NiO/Pt界面处都具有非常高的自旋转移效率。这提供了一个强大的平台,研究AF自旋泵和AF动力学,以及探索自旋操纵定制的结构,包括金属和绝缘铁磁体,反铁磁体和磁性材料。
英文摘要:
We observe highly efficient dynamic spin injection from Y$_3$Fe$_5$O$_{12}$ (YIG) into NiO, an antiferromagnetic (AF) insulator, via strong coupling, and robust spin propagation in NiO up to 100-nm thickness mediated by its AF spin correlations. Strikingly, the insertion of a thin NiO layer between YIG and Pt significantly enhances the spin currents driven into Pt, suggesting exceptionally high spin transfer efficiency at both YIG/NiO and NiO/Pt interfaces. This offers a powerful platform for studying AF spin pumping and AF dynamics as well as for exploration of spin manipulation in tailored structures comprising metallic and insulating ferromagnets, antiferromagnets and nonmagnetic materials.
Role of NiO in the nonlocal spin transport through thin NiO films on Y$_3$Fe$_5$O$_{12}$
在自旋输运实验中,自旋电流通过反铁磁(AFM)材料传播,反铁磁被视为一个主要的被动自旋导体不产生或增加任何自旋电流的系统。AFM NiO的自旋电流transmittance受磁场涨落的影响,在Néel温度处达到峰值,并通过降低温度而降低。为了研究原子力显微镜在局域和非局域自旋输运实验中的作用,我们发送自旋电流通过NiO的不同厚度放置在Y $_3$ Fe $_5$ O $_{12}$。自旋电流通过电或热梯度注入,并在很宽的温度和磁场强度范围内进行测量。透射作用反映在局部电注入信号的符号变化和通过降低温度而降低的所有其它信号的信号强度中。然而,热产生的信号显示出低于100 $\,$ K的额外的上升,其不受NiO厚度增加的影响。热导率的变化可能会影响这些信号。的温度和磁场的依赖性是类似的散装NiO,表明NiO本身有助于热诱导的自旋电流。
The effect of inserted NiO layer on spin-Hall magnetoresistance in Pt/NiO/YIG heterostructures
利用自旋霍尔磁电阻(SMR)研究了Pt/NiO/Y $_3$ Fe $_5$ O $_{12}$(Pt/NiO/YIG)异质结中反铁磁绝缘层(AFMI)的自旋电流输运.通过插入AFMI NiO层,SMR通过将温度降低到NiO的反铁磁有序状态而显著降低,这意味着AFM有序阻止而不是促进自旋电流输运。另一方面,YIG对Pt磁矩的磁邻近效应(MPE)与Pt中的自旋霍尔效应(SHE)纠缠在一起,可以有效地屏蔽这种效应,通过NiO的插入可以得到纯SMR。与其他反铁磁金属(AFM)或非铁磁金属(NM)相比,NiO的插入具有有效阻挡MPE和将自旋电流从Pt传输到YIG的双重作用。
The domain-wall/metal-electrode injection barrier in lithium niobate: Which electrical transport model fits best?
Institute of Applied Physics, Technische Universität Dresden(德累斯顿工业大学应用物理研究所);Experimental Physics V, Center for Electronic Correlations and Magnetism, University of Augsburg(奥格斯堡大学电子关联与磁学中心实验物理学V);Würzburg-Dresden Cluster of Excellence (EXC 2147) ctd.qmat – Complexity, Topology, and Dynamics in Quantum Matter(维尔茨堡-德累斯顿卓越集群(EXC 2147)ctd.qmat——量子物质的复杂性、拓扑和动力学);Institute for Photonic Quantum Systems (PhoQS), Department of Physics, University of Paderborn(帕德博恩大学物理学院光子量子系统研究所)
Imaging Antiferromagnetic Domains in Nickel-oxide Thin Films by Magneto-optical Voigt Effect
Fudan University(复旦大学);University of California, Davis(加州大学戴维斯分校);Dalian Institute of Chemical Physics, Chinese Academy of Sciences(中国科学院大连化学物理研究所);Shanghai Synchrotron Radiation Facility, Zhangjiang Laboratory, Chinese Academy of Sciences(中国科学院上海同步辐射光源张江实验室);Oakland University(奥克兰大学);Collaborative Innovation Center of Advanced Microstructures(先进微结构协同创新中心)
Spin pumping as a generic probe for linear spin fluctuations: demonstration with ferromagnetic and antiferromagnetic orders, metallic and insulating electrical states
Strongly nonlinear antiferromagnetic dynamics in high magnetic fields
Radboud University(拉德堡德大学);Kotel’nikov Institute of Radioengineering and Electronics, Russian Academy of Sciences(俄罗斯科学院科捷利尼科夫无线电电子学研究所);National Research University “Moscow Power Engineering Institute”(国立研究型莫斯科动力学院);Eindhoven University of Technology(埃因霍温理工大学);High Field Magnet Laboratory (HFML – EMFL)(强磁场实验室(HFML-EMFL));Saratov State University(萨马拉国立大学);Moscow Institute of Physics and Technology(莫斯科物理技术学院)