Spin-orbitronics and single pulse alloptical switching (AOS) of magnetization are two major successes of the fast advancing field of nanomagnetism in recent years, with high potential for enabling novel fast and energy-efficient memory and logic platforms. Fast current induced domain wall motion and single shot AOS have been individually demonstrated in different ferrimagnetic alloys. However, the stringent requirement for their composition control makes them challenging material for wafer scale production. Here, we demonstrate simultaneously fast current-induced domain wall motion and energy efficient AOS in a synthetic ferrimagnetic system based on Co/Gd2 multilayers. We firstly show AOS is present in its full composition range. We find current driven domain wall velocities over 2 km/s at room temperature conditions is achieved by compensating the total angular momentum through layer thickness tuning. Furthermore, analytical modelling of the current-induced domain wall motion reveals that Joule heating needs to be treated transiently to properly describe the current-induced domain wall motion for our sub-ns current pulses. Our studies establish Co/Gd based synthetic ferrimagnets to be a unique material platform for domain wall devices with access to ultrafast single pulse AOS 1.
References 1 Pingzhi Li, Thomas J Kools, Bert Koopmans and Reinoud Lavrijsen. Ultrafast racetrack based on compensated Co/Gd-based synthetic ferrimagnet with all-optical switching. arXiv preprint arXiv:2204.11595, 2022.