Speaker: Dingfu Shao, Hefei Institutes of Physical Science, Chinese Academy of Sciences

Host: Huaqing Huang (huanghq07@pku.edu.cn)

Time: 10:00-11:00 am, March 4, 2023, GMT+8

Venue: Tecent Meeting ID: 471-348-613

Abstract:

Electric currents carrying a net spin polarization are widely used in spintronics, whereas globally spin-neutral currents are expected to play no role in spin-dependent phenomena. Antiferromagnetic (AFM) materials usually support only spin-neutral currents, and hence are largely restricted in realistic spintronic applications, despite being robust against magnetic perturbations, not producing stray fields, and exhibiting ultrafast spin dynamics. Here we show, in contrast to this common expectation, spin-neutral currents in antiferromagnets can drive novel spin-dependent transport phenomena in antiferromagnetic tunnel junctions (AFMTJs), such as a tunneling magnetoresistance (TMR) and a tunneling anomalous Hall effect (TAHE) promising for accurate read-out, and a spin-transfer-torque (STT) crucial for efficient write-in. These phenomena are due to that the globally spin-neutral currents in antiferromagnets can host Néel spin currents, i.e. staggered spin currents flowing through different magnetic sublattices. Our works uncover the previously unexplored potentials of antiferromagnets and pave a new route to realize the efficient writing and reading of information for antiferromagnetic spintronics.

References:

[1] Ding-Fu Shao, et al., Spin-neutral currents for spintronics, Nature Communications 12, 7061 (2021).
[2] D. -F. Shao, et al., Spin-neutral tunneling anomalous Hall effect, Phys. Rev. B 106, L180404 (2022).
[3] D. -F. Shao, et al., Néel Spin Currents in Antiferromagnets, arXiv:2212.02367 (2022).

Biography：

邵定夫，研究员，博士生导师。2008年本科毕业于中国矿业大学，2013年博士毕业于中国科学院固体物理研究所，获中国科学院大学博士学位。2013年至2016年在中国科学院固体物理研究所担任助理研究员。2016年至2021年在美国内布拉斯加大学林肯分校访问研究，任博士后研究员、高级研究员。2021年获国家高层次人才计划资助。2021年12月全职回国，加入中国科学院合肥物质科学研究院固体物理研究所。邵定夫研究员长期从事量子材料与器件的理论研究，近期研究兴趣包括反铁磁电子学、二维铁电材料的自旋-轨道电子学等。目前发表学术论文60余篇，其中以第一作者或通讯作者身份在Physical Review Letters、Nature Communications、Science Advances 等期刊发表论文30余篇。

Source: School of Physics