Antiferromagnetic magnon spintronic based on non-reciprocal and non-degenerated ultra-fast spin-waves in the canted antiferromagnet {\alpha}-Fe2O3

TL;DR

This paper demonstrates the electrical detection of ultra-fast, non-reciprocal spin-waves in a canted antiferromagnet, advancing the development of antiferromagnetic magnonic devices with potential for faster, energy-efficient electronics.

Contribution

It reports the first electrical detection of coherent non-reciprocal spin-waves in a canted antiferromagnet using time-of-flight spectroscopy and inverse spin-Hall effects.

Findings

Spin-waves propagate up to 20 km/s in bulk and 6 km/s on surfaces.

Successful electrical detection of non-reciprocal spin-wave transport.

Demonstration of coherent spin-wave propagation in hematite ({2O3}).

Abstract

Spin-waves in antiferromagnets hold the prospects for the development of faster, less power-hungry electronics, as well as promising physics based on spin-superfluids and coherent magnon-condensates. For both these perspectives, addressing electrically coherent antiferromagnetic spin-waves is of importance, a prerequisite that has so far been elusive, because unlike ferromagnets,antiferromagnets couple weakly to radiofrequency fields. Here, we demonstrate the detection of ultra-fast non-reciprocal spin-waves in the dipolar-exchange regime of a canted antiferromagnet using both inductive and spintronic transducers. Using time-of-flight spin-wave spectroscopy on hematite ({\alpha}-Fe2O3), we find that the magnon wave packets can propagate as fast as 20 km/s for reciprocal bulk spin-wave modes and up to 6 km/s for surface-spin waves propagating parallel to the antiferromagnetic Neel vector. We finally achieve efficient electrical detection of non-reciprocal spin-wave transport using non-local inverse spin-Hall effects. The electrical detection of coherent non-reciprocal antiferromagnetic spin waves paves the way for the development of antiferromagnetic and altermagnet-based magnonic devices.