The “Serpentine” RTD Fluxgate Magnetometer

In this paper a new innovative fluxgate geometry has been characterized for the first time: the serpentine fluxgate. It has been obtained from a rod fluxgate with flexible microwire (CoFeSiB) folded in order to obtain two meanders at the center of the core. This new geometry has been directly compared with a straight fluxgate of the same core length and a straight fluxgate with a shorter core of the same length of the serpentine geometry. The Residence Times Difference (RTD) readout technique has been used because the most suitable for a single fluxgate. The results clearly show the improvement of noise immunity in the serpentine thanks to the longer core and a sensitivity similar or slightly less than the fluxgate with the shorter core. Thus, it is possible to obtain a compact fluxgate with some of the improvement given by a longer core. This study paves the way to new and unexpected configurations that can be created thanks to the flexibility of the core and that can be studied thanks to the RTD readout technique.