Waveguiding Effect in the Gigahertz Frequency Range in Pillar-based Phononic-Crystal Slabs

Phononic crystals (PnCs) have been studied extensively for two decades, as an enticing platform for ultrahigh-frequency signal processing. However, struggles with geometric scaling and efficient coupling of acoustic energy at the microscale have hindered the development of basic building blocks for devices. Through a systematic design approach, this study demonstrates waveguiding in pillar-based PnC slabs operating in the GHz regime, laying a foundation for more sophisticated signal-processing systems built of PnCs.