Magnetization dynamics and spin transport in compensated ferrimagnets

Spintronics is a multidisciplinary field whose central theme is the active manipulation of electron spins in solid-state systems. The core magnetic system for spintronics research has been ferromagnets since they serve as spin-polarizers/detectors and offer non-volatile memory and logic technologies. Recently, much effort has been expended in employing antiferromagnetic coupled systems as core elements because of their fast dynamics and efficient spin-torque generation. We will discuss the underlying mechanism of fast dynamics of compensated and uncompensated staggered spin moments, driven by magnetic fields or spin torques [1-3]. We will also discuss the increased efficiency of spin torques due the weakened spin dephasing in compensated ferrimagnets [4,5].

References
[1] T. Shiino et al, “Antiferromagnetic domain wall motion by spin-orbit torques”, Phys. Rev. Lett. 117, 087203 (2016).
[2] K.-J. Kim et al., “Fast domain wall motion in the vicinity of the angular momentum compensation temperature of ferrimagnets”, Nat. Mater. 16, 1187 (2017).
[3] Y. Hirata et al., “Vanishing skyrmion Hall effect at the angular momentum compensation temperature of a ferrimagnet”, Nat. Nanotechnol. 14, 232 (2019).
[4] J. Yu et al., “Long spin coherence length and bulk-like spin-orbit torque in ferrimagnetic multilayers”, Nat. Mater. 18, 29 (2019).
[5] T. Okuno et al., “Spin-transfer torques for domain wall motion in antiferromagnetically-coupled ferrimagnets”, Nat. Electron. 2, 389 (2019).