Time-dependent acceleration detection based on phononic sidebands in coupled electromechanical resonators

An efficient route for detecting time-dependent acceleration (TDA) is performed by employing electromechanically induced phononic sidebands in coupled frequency-mismatched electromechanical resonators. Based on the effects of difference frequency mixing and cascaded phonon-scattering in the electromechanical system, the nonlinear responses of normal and anomalous phononic sidebands are generated and enhanced in the strong inter-modal coupling regime. In the detection scheme, the information of TDA can be delivered to the spectral responses of acceleration-induced sidebands (AISs) since there is the piezoelectric coupling between the electromechanical resonators and a test mass that perceives external acceleration. Additionally, the amplitude of TDA could be separately detected by observing the amplitude variation of AISs, while the variation period of TDA could be read by monitoring the frequency of the prominent peak in the AIS signals. The distinctive nature of the electromechanical system in the environment of the cryogenic cooling enables an acceleration resolution of 12 µg (g = 9.8 m s−2) and a frequency resolution of 0.06 Hz.