Phononic BandGap coupled Bulk Acoustic wave Resonators

This paper presents the design, a (equivalent circuit) model and the characterization of coupled Bulk Acoustic wave Resonators (BARs) using Phononic BandGaps (PBGs) as coupling elements. Bar-type BARs are represented as 1D acoustic transmission lines to describe all harmonic acoustic extensional-mode resonances, and, further, the lumped network representation of PBGs with purely reactive elements defining the equivalent of non-propagating 1D metamaterials is discussed. Measured transmission data, in good agreement with their simulated counterparts, establish the validity of the derived models that thus effectively depict the behaviours of BARs, PBGs and PBG coupled BARs. This work opens perspective for the design and realisation of left-handed acoustic TLs by implementing mixed acoustic plasma media of the type demonstrated in this paper.