Magnetoresistive Fe19Ni81/Tb-Co medium with an internal magnetic bias

The magnetization reversal and magnetoresistance of two-layer exchange-coupled Fe19Ni81/Tb-Co films are studied. Amorphous Tb$_x$Co$_{100-x}$ layers with 30 $< x <$ 35 are found to have a uniaxial magnetic anisotropy and a rather high coercive force, which ensures magnetic biasing of the adjacent permalloy layers. In addition, the permalloy layers subjected to selective annealing exhibit a significant anisotropic magnetoresistance and a small magnetic hysteresis. These properties make it possible to consider the developed film structure as an effective magnetoresistive medium. This structure is used to form magnetic sensor samples that have an odd transfer function in the absence of external magnetic biasing.