Exchange coupling film having a plurality of local magnetic regions, magnetic sensor having the exchange coupling film, and magnetic head having the same

A magnetic sensor, comprising:

• a magnetic core having a ferromagnetic layer and an antiferromagnetic layer, the antiferromagnetic layer being disposed on the ferromagnetic layer and being exchange coupled with the ferromagnetic layer, the core having a plurality of local magnetic regions, each of the local regions having uniaxial magnetic anisotropy;
• and
• a magnetoresistance element magnetically coupled to the magnetic core and having a magnetoresistance film and a pair of electrodes, the pair of electrodes being electrically coupled to the magnetoresistance film;
• said uniaxial magnetic anisotropy of abutting local regions being different from each other, and a total magnetic anisotropy of the core being dispersed.

A magnetic head, comprising

• a magnetic core having a ferromagnetic layer, and an antiferromagnetic layer, the antiferromagnetic layer being disposed on the ferromagnetic layer, the antiferromagnetic layer being exchange coupled with the ferromagnetic layer, the core having a plurality of local magnetic regions, each of local regions having uniaxial magnetic anisotropy;
• and
• a coil which provides magnetic fields to the core;
• wherein the magnetic cores transfers the magnetic fields to a core tip potion of an air bearing surface;
• and
• wherein the uniaxial magnetic anisotropy of abutting local regions is different from each other, and total magnetic anisotropy of the core is dispersed.