Patent ID: 8089734

Claim:
A magnetoresistive element intended for detecting a magnetic signal written on a track of a recording medium, comprising: a first main shield portion and a second main shield portion; and an MR stack disposed between the first and second main shield portions, wherein: the first main shield portion, the MR stack, and the second main shield portion are arranged in a direction in which the track extends; the first main shield portion includes: a first main shield layer; a first antiferromagnetic layer that is disposed between the first main shield layer and the MR stack; and a first exchange coupling shield layer that is disposed between the first antiferromagnetic layer and the MR stack and is exchange-coupled to the first antiferromagnetic layer; the second main shield portion includes: a second main shield layer; a second antiferromagnetic layer that is disposed between the second main shield layer and the MR stack; and a second exchange coupling shield layer that is disposed between the second antiferromagnetic layer and the MR stack and is exchange-coupled to the second antiferromagnetic layer; the MR stack includes: a spacer layer made of a nonmagnetic material; a first free layer disposed between the first exchange coupling shield layer and the spacer layer; and a second free layer disposed between the second exchange coupling shield layer and the spacer layer; the first free layer is magnetically coupled to the first exchange coupling shield layer, whereby a direction of magnetization of the first free layer is controlled; and the second free layer is magnetically coupled to the second exchange coupling shield layer, whereby a direction of magnetization of the second free layer is controlled, the magnetoresistive element further comprising a pair of side shields disposed on opposite sides of the MR stack in a track width direction, between the first main shield portion and the second main shield portion, wherein each of the pair of side shields includes at least one shield-coupling magnetic layer that is in contact with and magnetically coupled to one of the first and second exchange coupling shield layers.