Fluxgate magnetic sensors with a readout strategy based on residence times measurements

We deal with analytical and experimental results on a highly sensitive fluxgate magnetometers wherein we exploit an efficient mode of operation that takes advantage of the inherent nonlinear (bistable) character of the core dynamics itself. Our approach, based on the passage time statistics of transitions to the stable steady states of the hysteresis loop, offers the possibility of using bias signals that have lower amplitude and frequency than those used in conventional fluxgate operation. The experiments are carried out on a laboratory prototype fluxgate, fabricated as a miniaturized device; this device is expected to lead to a MEMs implementation of a single fluxgate as well as a coupled ensemble of fluxgates.