Magnonics Based on Thin-Film Iron Garnets

Spin waves and their quanta magnons are collective excitation of electron spins in magnetic materials which can serve as information carriers for future low-power-consumption computing systems. Ferrimagnetic thin-film iron garnets are considered as an ideal platform for spin waves due to the low Gilbert damping. Here, we review the recent progress of magnonics based on thin-film iron garnets, including the yttrium iron garnet (YIG). Short-wavelength spin waves with dispersion relation governed by the exchange interaction have recently been reported in low damping YIG thin films. Periodical nanostructure thin-film iron garnets enrich the functionalities of magnonic crystals. In addition, pure spin currents in adjacent heavy metal layers could induce magnetic auto-oscillations and propagating spin waves in thin-film iron garnets. The broken inversion symmetry has also been found in thin-film iron garnets probed by chiral spin-wave group velocities. We conclude that thin-film iron garnets hold a bright future for magnon based logic devices and circuits.

Automated summary

Spin waves and magnons in magnetic materials are collective excitations of electron spins that can be used as information carriers for low-power computing systems. Thin-film iron garnets are ideal platforms for spin waves, with recent progress including short-wavelength spin waves in low damping YIG films.