Spintronics utilizes the electronic spin for information processing and microelectronics. Currently, spintronic devices are mostly based on ferromagnetic device architectures. In view of long-term perspectives to enable enhanced data processing speeds and downscaling for on-chip information processing, antiferromagnetic materials exhibit the key advantage over ferromagnets that their resonance frequency is generally in the terahertz regime. In compensated antiferromagnets, the absence of a net moment however strongly impedes simple access to their ultrafast dynamics and the development of ultra-fast antiferromagnet-based devices.

Researchers from CNRS/Thales lab in collaboration with Mainz (Germany) and NTNU (Norway) universities explored both theoretically and experimentally how one can access to the dynamics of an antiferromagnet by simple voltage measurements through the effect of spin-pumping from an antiferromagnet to an adjacent metal layer. They highlight that the Dzyaloshinskii Moriya interaction induced canted moment can strongly increase the spin-pumping response whilst preserving the high frequency response of antiferromagnetic materials. Another key result is that they can get access to the mode handedness through the sign of the spin-pumping signal. These results open the way towards the development of sub-THz frequency devices based on antiferromagnetic spintronic.

I. Boventer, H. T. Simensen, A. Anane, M. Kläui, A. Brataas, R. Lebrun
“Room temperature antiferromagnetic resonance and inverse spin-Hall voltage in a canted antiferromagnet”
Physical Review Letters 126, 187201 (2021)

This work was funded by the Horizon 2020 Framework Programme of the European Commission under FET-Open grant agreement no. 863155 (s-Nebula).

(Left panel) Spin-pumping voltage generated at the magnetic resonance in a bilayer of the canted antiferromagnet α-Fe2O3 capped with a 2 nm thin layer of platinum. (Right panel) Symmetry of the excited antiferromagnetic mode and sketch of the system.