On the Generation of Phononic Frequency Combs Using Defect Modes of Phononic Crystals

Abstract: This paper proposes a method for generating phononic frequency combs (PFCs) using defect-localized modes in a two-dimensional hexagonal phononic crystal. Localized vibration modes from a singular point defect produce evenly spaced spectral lines corresponding to PFCs. Numerical modelling reveals robust energy transfer under a single-tone drive, generating spectral sidebands. These results demonstrate defect engineering in phononic crystals as a tunable platform for PFC generation with significant applications in high-resolution sensing, timing, and quantum-acoustic technologies.