Antiferromagnetic half-skyrmions electrically generated and controlled at room temperature
Source abstract
Abstract
Abstract Topologically protected magnetic textures are promising candidates for information carriers in future memory devices, as they can be efficiently propelled at very high velocities using current-induced spin torques. These textures—nanoscale whirls in the magnetic order—include skyrmions, half-skyrmions (merons) and their antiparticles. Antiferromagnets have been shown to host versions of these textures that have high potential for terahertz dynamics, deflection-free motion and improved size scaling due to the absence of stray field. Here we show that topological spin textures, merons and antimerons, can be generated at room temperature and reversibly moved using electrical pulses in thin-film CuMnAs, a semimetallic antiferromagnet that is a testbed system for spintronic applications. The merons and antimerons are localized on 180° domain walls, and move in the direction of the current pulses. The electrical generation and manipulation of antiferromagnetic merons is a crucial step towards realizing the full potential of antiferromagnetic thin films as active components in high-density, high-speed magnetic memory devices.
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Research context
OpenAlex topics: Magnetic properties of thin films · Physics of Superconductivity and Magnetism · Advanced Condensed Matter Physics
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References (41)
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1. Kosterlitz, J. M. & Thouless, D. J. Ordering, metastability and phase transitions in two-dimensional systems. J. Phys. C 6, 1181 (1973).10.1088/0022-3719/6/7/010 ↗
2. Shinjo, T., Okuno, T., Hassdorf, R., Shigeto, K. & Ono, T. Magnetic vortex core observation in circular dots of permalloy. Science 289, 930–932 (2000).10.1126/science.289.5481.930 ↗
3. Kläui, M. et al. Current-induced vortex nucleation and annihilation in vortex domain walls. Appl. Phys. Lett. 88, 232507 (2006).10.1063/1.2209177 ↗
4. Jiang, W. et al. Blowing magnetic skyrmion bubbles. Science 349, 283–286 (2015).10.1126/science.aaa1442 ↗
5. Coïsson, M. Magnetic vortex chirality determination via local hysteresis loops measurements with magnetic force microscopy. Sci. Rep. 6, 29904 (2016).10.1038/srep29904 ↗
6. Gao, N. et al. Creation and annihilation of topological meron pairs in in-plane magnetized films. Nat. Commun. 10, 5603 (2019).10.1038/s41467-019-13642-z ↗
7. Gao, Y. et al. Spontaneous (anti)meron chains in the domain walls of van der Waals ferromagnetic Fe5−xGeTe2. Adv. Mater. 32, 2005228 (2020).10.1002/adma.202005228 ↗
8. Li, Z. et al. Field-free topological behavior in the magnetic domain wall of ferrimagnetic GdFeCo. Nat. Commun. 12, 5604 (2021).10.1038/s41467-021-25926-4 ↗
9. Wang, Y. et al. Electric field-driven rotation of magnetic vortex originating from magnetic anisotropy reorientation. Adv. Electron. Mater. 8, 2100561 (2021).10.1002/aelm.202100561 ↗
10. Zhang, S. et al. Direct imaging of an inhomogeneous electric current distribution using the trajectory of magnetic half-skyrmions. Sci. Adv. 6, eaay1876 (2020).10.1126/sciadv.aay1876 ↗
11. Göbel, B., Mook, A., Henk, J., Mertig, I. & Tretiakov, O. A. Magnetic bimerons as skyrmion analogues in in-plane magnets. Phys. Rev. B 99, 060407 (2019).10.1103/PhysRevB.99.060407 ↗
12. Göbel, B., Mertig, I. & Tretiakov, O. A. Beyond skyrmions: review and perspectives of alternative magnetic quasiparticles. Phys. Rep. 895, 1–28 (2021).10.1016/j.physrep.2020.10.001 ↗
13. Barker, J. & Tretiakov, O. A. Static and dynamical properties of antiferromagnetic skyrmions in the presence of applied current and temperature. Phys. Rev. Lett. 116, 147203 (2016).10.1103/PhysRevLett.116.147203 ↗
14. Thiele, A. A. Steady-state motion of magnetic domains. Phys. Rev. Lett. 30, 230–233 (1973).10.1103/PhysRevLett.30.230 ↗
15. Tretiakov, O. A. et al. Dynamics of domain walls in magnetic nanostrips. Phys. Rev. Lett. 100, 127204 (2008).10.1103/PhysRevLett.100.127204 ↗
16. Tveten, E. G., Qaiumzadeh, A., Tretiakov, O. A. & Brataas, A. Staggered dynamics in antiferromagnets by collective coordinates. Phys. Rev. Lett. 110, 127208 (2013).10.1103/PhysRevLett.110.127208 ↗
17. Kolesnikov, A. G. et al. Composite topological structure of domain walls in synthetic antiferromagnets. Sci. Rep. 8, 15794 (2018).10.1038/s41598-018-33780-6 ↗
18. Sort, J. et al. Imprinting vortices into antiferromagnets. Phys. Rev. Lett. 97, 067201 (2006).10.1103/PhysRevLett.97.067201 ↗
19. Wu, J. et al. Direct observation of imprinted antiferromagnetic vortex states in CoO/Fe/Ag(001) discs. Nat. Phys. 7, 303–306 (2011).10.1038/nphys1891 ↗
20. Chmiel, F. P. et al. Observation of magnetic vortex pairs at room temperature in a planar α-Fe2O3/Co heterostructure. Nat. Mater. 17, 581–585 (2018).10.1038/s41563-018-0101-x ↗
21. Gao, S. et al. Fractional antiferromagnetic skyrmion lattice induced by anisotropic couplings. Nature 586, 37–41 (2020).10.1038/s41586-020-2716-8 ↗
22. Jani, H. et al. Antiferromagnetic half-skyrmions and bimerons at room temperature. Nature 590, 74–79 (2021).10.1038/s41586-021-03219-6 ↗
23. Wadley, P. et al. Electrical switching of an antiferromagnet. Science 351, 587–590 (2016).10.1126/science.aab1031 ↗
24. Grzybowski, M. J. et al. Imaging current-induced switching of antiferromagnetic domains in CuMnAs. Phys. Rev. Lett. 118, 057701 (2017).10.1103/PhysRevLett.118.057701 ↗
25. Olejník, K. et al. Antiferromagnetic CuMnAs multi-level memory cell with microelectronic compatibility. Nat. Commun. 8, 15434 (2017).10.1038/ncomms15434 ↗
26. Olejník, K. et al. Terahertz electrical writing speed in an antiferromagnetic memory. Sci. Adv. 4, eaar3566 (2018).10.1126/sciadv.aar3566 ↗
27. Wadley, P. et al. Current polarity-dependent manipulation of antiferromagnetic domains. Nat. Nanotechnol. 13, 362–365 (2018).10.1038/s41565-018-0079-1 ↗
28. Kašpar, Z. et al. Quenching of an antiferromagnet into high resistivity states using electrical or ultrashort optical pulses. Nat. Electron. 4, 30–37 (2021).10.1038/s41928-020-00506-4 ↗
29. Zubáč, J. et al. Hysteretic effects and magnetotransport of electrically switched CuMnAs. Phys. Rev. B 104, 184424 (2021).10.1103/PhysRevB.104.184424 ↗
30. Krizek, F. et al. Molecular beam epitaxy of CuMnAs. Phys. Rev. Mater. 4, 014409 (2020).10.1103/PhysRevMaterials.4.014409 ↗
31. Janda, T. et al. Magneto-Seebeck microscopy of domain switching in collinear antiferromagnet CuMnAs. Phys. Rev. Mater. 4, 094413 (2020).10.1103/PhysRevMaterials.4.094413 ↗
32. Wadley, P. et al. Control of antiferromagnetic spin axis orientation in bilayer Fe/CuMnAs films. Sci. Rep. 7, 11147 (2017).10.1038/s41598-017-11653-8 ↗
33. Reimers, S. et al. Defect-driven antiferromagnetic domain walls in CuMnAs films. Nat. Commun. 13, 724 (2022).10.1038/s41467-022-28311-x ↗
34. Máca, F. et al. Physical properties of the tetragonal CuMnAs: a first-principles study. Phys. Rev. B 96, 094406 (2017).10.1103/PhysRevB.96.094406 ↗
35. Kurebayashi, D. & Tretiakov, O. A. Skyrmion nucleation on the surface of a topological insulator. Phys. Rev. Res. 4, 043105 (2022).10.1103/PhysRevResearch.4.043105 ↗
36. Hertel, R. & Schneider, C. M. Exchange explosions: magnetization dynamics during vortex–antivortex annihilation. Phys. Rev. Lett. 97, 177202 (2006).10.1103/PhysRevLett.97.177202 ↗
37. Gomonay, O., Jungwirth, T. & Sinova, J. High antiferromagnetic domain wall velocity induced by Néel spin–orbit torques. Phys. Rev. Lett. 117, 017202 (2016).10.1103/PhysRevLett.117.017202 ↗
38. Tomasello, R. et al. A strategy for the design of skyrmion racetrack memories. Sci. Rep. 4, 6784 (2014).10.1038/srep06784 ↗
39. Geng, L. D. & Jin, Y. M. Magnetic vortex racetrack memory. J. Magn. Magn. Mater. 423, 84–89 (2017).10.1016/j.jmmm.2016.09.062 ↗
40. Juge, R. et al. Helium ions put magnetic skyrmions on the track. Nano Lett. 21, 2989–2996 (2021).10.1021/acs.nanolett.1c00136 ↗
41. Yu, H., Xiao, J. & Schultheiss, H. Magnetic texture based magnonics. Phys. Rep. 905, 1–59 (2021).10.1016/j.physrep.2020.12.004 ↗