Inspired by the recent achievements of the strong magnons- and spin textures-photons coupling via dipolar interaction, the coupling between magnons and the local resonances of spin textures through direct exchange interaction is expected but not real
ized yet. In this work, we demonstrated the coherent coupling between propagating magnons and local skyrmion resonances. Besides the Rabbi coupling gap (RCG) in the frequency field dispersion, a magnonic analog of polariton gap, polaragnonic band gap (PBG), is also observed in the frequency-wavenumber dispersion. The realization of coupling requires the gyrotropic skyrmion modes to satisfy not only their quantum number larger than one but also their chirality opposite to that of magnons. The observed PBG and RCG can be controlled to exist within different Brillouin zones (BZs) as well as at BZ boundaries. The coupling strength can approach the strong regime by selecting the wavenumber of propagating magnons. Our findings could provide a pure magnonic platform for investigating quantum optics phenomena in quantum information technology.
Strong coupling between magnons and cavity photons was studied extensively for quantum electrodynamics in the past few years. Recently, the strong magnon-magnon coupling between adjacent layers in magnetic multilayers has been reported. However, the
strongly coupled magnons confined in a single nanomagnet remains to be revealed. Here, we report the interaction between different magnon modes in a single magnonic cavity. The intermodel coupling between edge and center magnon modes in the strong coupling regime was approached with a maximum coupling strength of 0.494 GHz and cooperativity of 60.1 with a damping of 1X10-3. Furthermore, it is found that the coupling strength is highly dependent on the geometric parameters of the magnonic cavity. Our findings could greatly enrich the still evolving field of quantum magnonics.
