Magnon chirality refers to the precessional handedness of magnetization around the external magnetic field, which is fixed as right-handed in ferromagnets. Compensated ferrimagnets accommodate parallel and antiparallel configurations of net magnetization and angular momentum, and thus serve as an ideal platform for studying magnon chirality. Through performing spin-torque ferromagnetic resonance experiments, we experimentally study the reversal of low-frequency magnon chirality across the magnetization and angular momentum compensation temperatures in a bilayer. In particular, we demonstrate that dampinglike spin torque could sensitively excite and detect the reversal of low-frequency magnon chirality. By solving the coupled Landau-Lifshitz-Gilbert equations, the close correlation between the reversal of low-frequency magnon chirality and the sign of net angular momenta is …
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.133.166705