Electric field control of Néel spin–orbit torque in an antiferromagnet

Abstract

Electric field control of spin–orbit torque in ferromagnets1 has been intensively pursued in spintronics to achieve efficient memory and computing devices with ultralow energy consumption. Compared with ferromagnets, antiferromagnets2,3 have huge potential in high-density information storage because of their ultrafast spin dynamics and vanishingly small stray field4,5,6,7. However, the manipulation of spin–orbit torque in antiferromagnets using electric fields remains elusive. Here we use ferroelastic strain from piezoelectric materials to switch the uniaxial magnetic anisotropy in antiferromagnetic Mn2Au films with an electric field of only a few kilovolts per centimetre at room temperature. Owing to the uniaxial magnetic anisotropy, we observe an asymmetric Néel spin–orbit torque8,9 in the Mn2Au, which is used to demonstrate an antiferromagnetic ratchet. The asymmetry of the Néel spin–orbit torque and the corresponding antiferromagnetic ratchet can be reversed by the electric field. Our finding sheds light on antiferromagnet-based memories with ultrahigh density and high energy efficiency.

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Fig. 1: Schematic of ferroelastic strain switching of UMA driven by electric fields in antiferromagnet/PMN-PT(011) structure.
Fig. 2: E-dependent Mn L-edge XMLD signals of Mn2Au.
Fig. 3: Ratchet-like NSOT in Mn2Au with UMA.
Fig. 4: E-control of Jth for NSOT in Mn2Au.

Data availability

The data that support the plots within this paper and other findings of this study are available from the corresponding author on reasonable request.

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Acknowledgements

We are grateful for discussions with J. H. Han, D. Z. Hou and P. Yu. C.S. acknowledges the support of the Beijing Innovation Center for Future Chips, Tsinghua University and the Young Chang Jiang Scholars Programme. The XMLD measurements were carried out at Beamline BL08U1A of SSRF. This work was supported by the National Key R&D Programme of China (grant no. 2017YFB0405704), the National Natural Science Foundation of China (grant nos. 51871130, 51571128, 51671110 and 51831005) and the 973 project of the Ministry of Science and Technology of China (grant no. 2015CB921402).

Author information

C.S. and X.C. designed the experiment; X.C. and X.Z. fabricated the samples and collected all of the data. X.C., Y.B., H.L., Y.S., Y.Y. and Y.Z. analysed the data. R.C., J.Z. and Y.W. contribute to theoretical support. C.S. and F.P. supervised this study. All the authors discussed the results and prepared the manuscript.

Correspondence to Cheng Song or Feng Pan.

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Supplementary information

Supplementary Information

Supplementary Figs. 1–10, Supplementary Table 1 and Supplementary refs. 1–12.

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