Control of Demagnetizing Field and Magnetostatic Coupling in FeCoV Wires for Zero-speed Sensor

In this paper, a measurement of the effect of the demagnetizing field and a method of reducing these disadvantages by etching both ends of the wire are studied. A magnetization reversal in magnetic wires with bistable magnetization states induces pulse voltage in a pickup coil. Amplitude of the voltage does not depend on frequency of an applied magnetic field down to zero. The magnetization switching is accompanied with a large Barkhausen jump. The twisted Vicalloy wire reveals a uniaxial magnetic anisotropy along the wire direction. A magnetization of the hard core is not normally switched in sensor applications. The symmetric output and higher voltages in Vp and Vap obtained from the etched wire are preferable for the sensor applications, which cannot be achieved from the as-prepared wire. It is suggested that edge effects of a demagnetizing field and a magnetostatic coupling can be reduced by etching the soft layer at both ends of the wire.