Electrically tunable plasmomechanical oscillators for localized modulation, transduction, and amplification

interactions with high speed and subdiffraction spatial resolution. However, realizing their potential requires developing active plasmomechanical systems that can localize their functionality to the level of an individual subwavelength plasmonic resonator. Here, we present an active, electrically tunable plasmomechanical system that uses a localized-gap plasmonic resonator to mediate optical, thermal, and mechanical interactions within a subwavelength footprint. Our device enables facile electromechanical modulation of localized plasmons, selective subdiffraction transduction of nanomechanical motion, and functions as a plasmomechanical oscillator that can be injection-locked to, and thus amplify, weak external stimuli. These functionalities benefit applications in nanomechanical sensing, spatial light modulators, and reconfigurable metasurfaces.