Fig. 1. （a）Schematic of the linearly coupled magnon（m）and photon（a）system. g is the coupling strength，κ_m and κ_a are the dissipation rates of magnon and microwave cavity modes.（b）Four kinds of coupling regimes separated by the relative strength between the coupling rate and dissipation rates of photon and magnon subsystem.（c）eigenfrequency’s real partsRe（ω_1，2） of the energy splitting.（d）eigenfrequency’s imaginary parts Im（ω_1，2）of mode’s damping exchange.

Fig. 2. （a）Schematic of the waveguide assembly cavity.（b-d）impact of sample thickness and cavity length on the coupling strength g.（b） d = 0.5 mm，W = 85 mm.（c） d = 1 mm，W = 85mm.（d）d = 0.5 mm，W = 242 mm.（d）functions of |S₂₁| and（ω - ω_c）/2π in three different cases^［71］

Fig. 3. （a）The A-P-M device is consist of a passive cavity（P），an active cavity（A）with a voltage tuneable gain（G_n），and an YIG sphere with magnons（M）.（b）The A-P cavity circuit’s Q-factor and G_nare respectively tunable up to 81，500 and 360，000，with the increase of V.（c）| S₂₁ | spectra measured（circles）and fitted（curve）at ∆ = 0 and V = 7V.（d）| S₂₁ | spectra measured at ∆ = 0 and V = 7V with various Rabi frequencies Ω_f determined from the mode splitting.（e）The ratio of Rabi frequencies Ω_f/Ω₀ which is measured（circles）and calculated（curve）is changing with the increase of V and G_n . The maximum uncertainty caused by the error from fitting the Rabi frequency is shown by the error bar^［72］

Fig. 4. （a）Schematic diagram illustrates a tunable A-P-M device consisting of an active cavity（A）and a varactor-loaded passive cavity（P），where Vc is the control voltage applied to the varactor and V is fixed at 7V.（b）The dispersions of the magnon quintuplet as a function of external field H with Vc = -3 V.（c）Magnon quintuplet evolution with control voltage Vc for an external field of 120 mT（indicated by arrow in panel（b））^［74］

Fig. 5. （a）Radiative damping dominates energy dissipation in magnon mode when coupled with photon mode in a circular waveguide cavity，as shown in（a）. Experimental setup of the coupled system is shown in（b）. Simulated LDOS ρ_{⊥ at d=0mm and d=6.5mm are shown in（c）and（e），respectively. Measured and calculated linewidth-frequency relations are shown in（d）and（f），with black circles indicating measured intrinsic linewidths^［75］}

Fig. 6. Analogue of dynamic Hall effect demonstrated in a cavity magnon polariton system with external static magnetic field along z-direction. Polariton flow and charge current exhibit similar deflection patterns in y-direction，shown in（a）and（b）. Microwave transmission spectra and output voltage measurements at 0mT and 203mT are shown in（c）-（f），with solid lines indicating results from the dynamic Hall model. Experimental setup（g）includes a mechanical phase shifter，and（h）shows transmission amplitude mapping with different phase differences between input ports. Logic table for response of side modes（SMs）and central mode（CM）is shown in（i）^［83］

Fig. 7. Schematic diagrams of electromagnetic absorption limitations in symmetric two-port and perfect absorption in singleport systems are shown in（a）and（b），respectively.（c）Coherent perfect absorption（CPA）strategy is shown for a two-port system.（d）MIPA system is shown，with near-perfect absorption achieved through the interference between hybrid photonmagnon modes. Energy level schematic is shown in（e）. Squared amplitudes of reflection and transmission at θ = 0◦ and 90◦ are shown in（f）and（g）. Theoretical function of maximal absorption rate is shown in（h），with green and yellow indicating the parameters of currently used and modified intersecting cavities，and white dashed line indicating maximal absorption rate over 90%^［85］