Broadband Phonon Resonance Spectrum in Host–Guest Resonator Arrays via Nonlocal Coupling

Resonance mechanisms offer a promising way to control phonon transport at the nanoscale, but realization of broadband phonon resonance remains challenging due to the narrow band nature of individual resonators. Here, it is demonstrated in the host–guest system that broadband phonon resonance can be achieved by introducing nonlocal coupling between multiple resonator arrays. The effects of coupling strength between the host cage and guest atom as well as the mass of the guest atom on the resonance bandwidth and phonon localization are investigated in detail via phonon wave packet simulations. By tuning these parameters while keeping resonant frequencies constant, it is found that stronger host–guest coupling and heavier guest atoms lead to a broader resonance spectrum and enhanced localization. More importantly, the introduction of nonlocal coupling between individual resonators with different resonant frequencies results in collective resonance behavior, giving rise to a broadband and smooth resonant spectrum. These results offer insights into harnessing nonlocal coupling in multiresonator structures to realize broadband phonon control in advanced phononic metamaterials.