Oleg A. Tretiakov (U of New South Wales): Topotronics with Magnetic Topological Materials

I will discuss topological magnetic textures, such as skyrmions, half-skyrmions (merons), bimerons and their anti-particles, which constitute tiny whirls in the magnetic order. They are promising candidates as information carriers for next generation electronics (thus called topotronics), as they can be efficiently propelled at very high velocities employing current-induced spin torques [1]. First, I will talk about skyrmions [2,3] and bimerons [4,5] in ferromagnetic systems coupled to heavy metals and topological materials. Then I will show that antiferromagnets can also host a variety of these textures, which have gained significant attention because of their potential for terahertz dynamics, deflection free motion [6], and improved size scaling due to the absence of stray fields. Finally, I will demonstrate 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 test-bed system for spintronic applications [7].

1. B. Göbel, I. Mertig, and O. A. Tretiakov, Phys. Rep. 895, 1 (2021).
2. D. Kurebayashi and O. A. Tretiakov, Phys. Rev. Research 4, 043105 (2022).
3. M.-G. Han, F. Camino, P. A. Vorobyev, J. Garlow, R. Rov, T. Söhnel, J. Seidel, M. Mostovoy, O. A. Tretiakov, Y. Zhu, Nano Lett. 23, 7143 (2023).
4. B. Göbel, A. Mook, I. Mertig, and O. A. Tretiakov, Phys. Rev. B 99, 060407(R) (2019).
5. K. Ohara, O. A. Tretiakov, et al., Nano Lett. 22, 8559 (2022).
6. J. Barker and O. A. Tretiakov, Phys. Rev. Lett. 116, 147203 (2016).
7. O. J. Amin, O. A. Tretiakov, et al., Nature Nano. 18, 849 (2023).