Magnetic field sensors based on the foil of amorphous cobalt alloy and NiMnGa martensite single-crystals

The problem of creation of small size wideband sensitive sensors of magnetic field with a narrow directional diagram and a small coefficient of thermal drift is actual and requires searching for new magnetic materials. We present the results of the development of the flux-gate sensors with the 20 μm magnetic core of amorphous foils of ММ-3Со and ММ-5Со cobalt alloys and magnetoelectric transducers with magnetic field sensitive element of NiMnGa martensite single-crystal. The peculiarities of our sensors are the usage of the parametric amplification and related to it the strong nonlinearity of the dependences of magnetic permeability of amorphous foil and NiMnGa single-crystal magnetostriction on the magnetic field amplitude.