Piezoelectric harvester scavenges energy from cavity of phononic crystal

We propose a model of a piezoelectric power harvester that scavenges energy from the cavity of a phononic crystal (PnC). The band structure of the PnC with a cavity is calculated by super-cell technique. The energy is collected in the cavity when the frequency of the cavity defect mode appears inside the band gap. As a result, the harvester can transform mechanical energy into electric energy efficiently.