Author(s): Yihang Duan, Shangyuan Wang, and Ka Shen A recent study reporting interferencelike patterns in nonlocal spin-wave measurements on hematite [Sheng et al., Control of spin currents by magnon interference in a canted antiferromagnet, Nat. Phys. 21, 740 (2025).] suggested the existence of a hidden ultrafast spin-wave mode at tens of gigahertz.… [Phys. Rev. Lett. 137, 126705] Published Wed Sep 16, 2026