In this study, the coil-less fluxgate effect in Co71Fe1Mo1Mn4Si14B9 amorphous ribbon was investigated. The coil-less fluxgate is a new type of fluxgate sensor without a coil. It is based on helical anisotropy and deep circumferential magnetic saturation in the ferromagnetic fluxgate core. Coil-less fluxgate measurements were performed in as-cast and annealed ribbons at 480 mA current with 3, 12.5 and 25 rad/m torsion. The second harmonic of the output voltage detected from the ends of the wire show a linear variation in the low magnetic field region. The sensitivity of the current annealed ribbons in the presence of 25 rad/m torsion is about 570 V/T, which is comparable with previously reported fluxgate sensitivity values. The presented sensor has no coil so it is much easier to reduce the size of the sensor and easy to fabricate it.
