Probing magnon–magnon coupling in exchange coupled Y$$_3$$Fe$$_5$$O$$_{12}$$/Permalloy bilayers with magneto-optical effects
Yuzan Xiong, Yi Li, Mouhamad Hammami, Rao Bidthanapally, Joseph Sklenar, Xu‐Feng Zhang, Hongwei Qu, G. Srinivasan, John E. Pearson, Axel Hoffmann, V. Novosad, Wei Zhang
Abstract
(YIG)/Permalloy (Py) coupled bilayers. The measurement is achieved via a heterodyne detection of the coupled magnetization dynamics using a single wavelength that probes the magneto-optical Kerr and Faraday effects of Py and YIG, respectively. Clear features of the MIT effect are evident from the deeply modulated ferromagnetic resonance of Py due to the perpendicular-standing-spin-wave of YIG. We develop a phenomenological model that nicely reproduces the experimental results including the induced amplitude and phase evolution caused by the magnon-magnon coupling. Our work offers a new route towards studying phase-resolved spin dynamics and hybrid magnonic systems.