A Mode-Localized Lorentz Force Magnetometer with 1.6μT/√Hz Resolution

摘要

This paper for the first time reports a resonant magnetometer based on the mode localization phenomenon. The proposed sensor utilizes a 3 degrees-of-freedom (DoF) weakly coupled resonators (WCRs) as the mechanical sensing element, with massive grill structures on both sides for converting magnetic field strength to stiffness perturbation. Stiffness perturbation will cause a drastic variation in the mode shape owing to the mode localization phenomenon. We use the amplitude ratio (AR) instead of the frequency as the readout metric, and the sensitivity of AR is 7800 times higher than that of frequency. And the best resolution of the magnetometer is 1.6μT/√Hz in the range of 90mT.