Nonlinear tuning of magnon–photon coupling through pump-induced magnon modes

We investigate the nonlinear tuning of magnon–photon interactions in a dissipative magnon–photon system by introducing a nonlinear pump-induced magnon (PIM) mode. By aligning the pump microwave frequency with either the magnon or cavity mode, we identify two distinct dynamical responses modulated by the PIM. When the pump frequency aligns with the magnon mode frequency, the overall coupling strength of the three-mode system increases with pump power, showing an improvement of 36% at a pump power of 18 dBm. When the pump frequency aligns with the cavity frequency, the coherent coupling between the PIM mode and the magnon mode competes with the dissipative magnon–photon interaction, suppressing the latter and driving the system toward a coherent coupling regime. These results demonstrate a viable approach for controlling the coupling strength and switching between dissipative and coherent coupling regimes via nonlinear magnon interactions, offering potential for tunable magnonic devices.