Ultrafast Switching of Antiferromagnets via Spin-transfer Torque

TL;DR

This paper demonstrates that ultrafast, picosecond-scale switching of antiferromagnetic order can be achieved using spin-transfer torque from short current pulses, enabling potential THz-frequency applications.

Contribution

It introduces a classical pendulum model for antiferromagnetic dynamics under spin-transfer torque, revealing optimal switching conditions and broadening understanding of ultrafast magnetic control.

Findings

Switching occurs if the pendulum gains enough kinetic energy during the pulse.

Optimal switching depends on pulse duration and strength.

Provides a pathway for THz-frequency spintronic devices.

Abstract

Picosecond switching of the staggered antiferromagnetic order is shown to be realizable through spin-transfer torques from a short current pulse. The coupled dynamics of sublattice magnetization is mapped onto a classical pendulum subject to gravity and a driving pulse, where switching occurs if the pendulum acquires sufficient kinetic energy during the pulse to overcome the maximum of the effective gravity potential. The optimal switching scheme is explored through the dependence of switch angle and magnetic loss on the duration and strength of the current pulse. The physics discussed here provides a general route towards multi-functional THz applications via the spin-transfer torque in antiferromagnetic materials.