Magnetic field

Physics

Chirality (physics)

Mathematical analysis

Current (fluid)

Antiferromagnetism

Domain wall (magnetism)

Magnetic domain

Materials science

Nambu–Jona-Lasinio model

Spintronics

Condensed matter physics

Magnetization dynamics

Magnetization

Mathematics

Domain (mathematical analysis)

Chiral symmetry breaking

Quantum mechanics

Quark

Ferrimagnetism

Ferromagnetism

Thermodynamics

Physical Review Letters

Owing to the difficulty in detecting and manipulating the magnetic states of antiferromagnetic materials, studying their switching dynamics using electrical methods remains a challenging task. By employing heavy-metal--rare-earth--transition-metal alloy bilayers, we experimentally study current-induced domain wall dynamics in an antiferromagnetically coupled system. We show that the current-induced domain wall mobility reaches a maximum at the angular momentum compensation point. With experiment and modeling, we further reveal the internal structures of domain walls and the underlying mechanisms for their fast motion. We show that the chirality of the ferrimagnetic domain walls remains the same across the compensation points, suggesting that spin orientations of specific sublattices rather than net magnetization determine Dzyaloshinskii-Moriya interaction in heavy-metal--ferrimagnet bilayers. The high current-induced domain wall mobility and the robust domain wall chirality in compensated ferrimagnetic material opens new opportunities for high-speed spintronic devices.

Current-Induced Domain Wall Motion in a Compensated Ferrimagnet