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Multichannel coupling in hybrid systems makes an attractive testbed not only because of the distinct advantages entailed by each constituent mode but also because the opportunity to leverage interference among the various excitation pathways. Here, via combined analytical calculation and experiment, we demonstrate that the phase of the magnetization precession at the interface of a coupled yttrium iron garnet (YIG)/permalloy (Py) bilayer is collectively controlled by the microwave photon field torque and the interlayer exchange torque, manifesting a coherent, dual-channel excitation scheme that effectively tunes the magneto-optical spectrum. The different torque contributions vary with frequency, external bias field, and type of interlayer coupling between YIG and Py, which further results in destructive or constructive interferences between the two excitation channels, and hence selective suppression or amplification of the hybridized magnon modes. 

Isolated actuated signalized intersection is a pressing challenge for conventional eco-approach methods, due to the ever-changing signal timing strategy. This research proposes an optimal control based eco-approach method tailored to tackle this challenge. The proposed method bears the following features: i) capable of predicting the ever-changing actuated signal timing; ii) with enhanced fuel efficiency via proactively catching a feasible passing time window; iii) with real-time computation efficiency for implementation. Simulation results demonstrate that the proposed method enhances fuel efficiency by 9.1%, reduces stop count by 14.8%, and enhances safety performance by 317.14%, compared to conventional human-driven vehicles. The passing time window predic- tion capability is confirmed with an accuracy of 3.1 s. All the aforementioned benefit is at a cost of a minimal travel time increase of 5.5 s. Moreover, the average computation time of the proposed method is 12 ms, demonstrating its readiness for field implementation. 

Abstract A magnon and a phonon are the quanta of spin wave and lattice wave, respectively, and they can hybridize into a magnon polaron when their frequencies and wavenumbers match close enough the values at the exceptional point. Guided by an analytically calculated magnon polaron dispersion, dynamical phase-field simulations are performed to investigate the effects of magnon polaron formation on the attenuation of a bulk acoustic wave in a magnetic insulator film. It is shown that a stronger magnon–phonon coupling leads to a larger attenuation. The simulations also demonstrate the existence of a minimum magnon–phonon interaction time required for the magnon polaron formation, which is found to decrease with the magnetoelastic coupling coefficient but increase with the magnetic damping coefficient. These results deepen the understanding of the mechanisms of acoustic attenuation in magnetic crystals and provide insights into the design of new-concept spin interconnects that operate based on acoustically driven magnon propagation.