Radio frequency magnetic field detection using piezoelectric coupled microcantilevers

We report on measurement of radio frequency magnetic fields using a stack of piezoelectric material coupled with microcantilevers. The time varying magnetic field of the radio frequency excitation induces a voltage in the piezoelectric stack and the resulting mechanical vibration is amplified by microcantilevers coupled to it under resonance and is measured by a laser–photodetector system. The method of measurement combines the objectives of a radio signal sensor and a microfilter. We have detected magnetic fields of the order of 1.8 pT at room temperature conditions. The results can lead to the development of novel micromechanical radio signal sensors.