Coupled Resonators as a New Transduction Principle for Ultraprecise Sensors

Abstract:
This paper summarizes the fast evolving field of sensors based on coupled resonators. When two or more microresonators are coupled and a perturbation is introduced, the resonant frequencies, amplitude ratios and eigenstates change. When using eigenstate change or amplitude ratios used as output signals, the sensitivity with respect to the perturbation is orders of magnitude higher compared to resonant frequency shift, which is the conventional output metric for resonant sensors. The perturbation can be caused by a physical quantity to be measured that changes the spring constant or by a docking event of a biochemical analyte that changes the effective mass of a resonator. Recent developments are reviewed as well as open research questions and expected future developments are discussed.