Magnetic field sensing by an electrostrictive/magnetostrictive composite resonator

A magnetic field sensor made of an electrostrictive plate and magnetostrictive layers is investigated. Its response to an external field suggests that the sensor has sensitivity high enough to detect terrestrial field. An analysis to predict the basic behavior was developed. Deviation of the experiments from the theoretical curve was attributed to complicated domain structures. Performance of a feedback system to improve the characteristics is demonstrated. It is expected that the performance would be improved appreciably by fabricating them by a thin film process.