Sub-terahertz electromechanics

Electromechanical resonators operating in the sub-terahertz regime could be of use in the development of future communication systems because they support extremely fast data rates. Such resonators are also of interest in studying quantum phenomena of mechanical entities, as they can maintain the quantum ground state at kelvin temperatures rather than the millikelvin temperatures demanded by gigahertz resonators. Here we report microelectromechanical resonators operating beyond 100 GHz. By incorporating a millimetre-wave dual-rail resonator into a thickness-shear-mode micromechanical system, we achieve efficient electromechanical transduction through enhanced on-chip impedance matching, which is key to revealing the infinitesimal displacements of these sub-terahertz mechanical modes. Our devices are based on commercially available z -cut lithium niobate thin films and patterned using standard semiconductor fabrication processes.