Speaker
Description
Magnonics — the study of spin waves — is a promising field for developing energy-efficient future information technologies. In this project, we explored magnon transport in altermagnetic materials, a novel class of collinear and compensated magnetic systems with unique spin symmetries that allow for many useful spintronic phenomena.
Our experiments confirmed the transfer of spin current across interfaces between a heavy metal and an altermagnet (Pt|Ba₂CoGe₂O₇), which is a critical process for all-electrical magnon excitation and detection. Notably, we observed anisotropy in this transfer, suggesting that magnon transport in altermagnets may also be anisotropic. We also successfully fabricated devices for all-electrical magnon excitation and detection and conducted preliminary measurements. However, further optimization of measurement techniques will be required to improve the signal-to-noise ratio.
Using THz spectroscopy, we also investigated coherent magnon propagation in α-Fe₂O₃, another altermagnetic candidate. Our results provided clear evidence of coherent magnons and their group velocity, offering new insights into their fundamental properties. These findings lay the groundwork for future studies on anisotropy, external field effects, and temperature dependence.
Overall, this work not only deepens our understanding of altermagnets but also opens new pathways for their application in spintronic devices.