Magnetoresistive sensor, thin-film read/write head, and magnetic recording apparatus using the sensor

A magnetoresistive element, comprising:

• an antiferromagnetic layer;
• a second magnetic layer on the antiferromagnetic layer;
• a non-magnetic interlayer on the second magnetic layer;
• and
• a first magnetic layer on the non-magnetic interlayer;
• wherein said first magnetic layer extends in a track width direction, and includes a specific region at each end of the first magnetic layer in the track width direction;
• the saturation magnetization of each said specific region is smaller than that at a central part of said first magnetic layer, and
• each of said specific regions has a width Xe defined by the equation 0.08≦Xe/Twr≦0.2, where Twr denotes the track width of the first magnetic layer.

A magnetoresistive head, comprising:

• an upper shield;
• a lower shield;
• a magnetoresistive element provided between said upper and lower shields;
• and
• a magnetic domain controlling film provided at both ends of the magnetoresistive element in a track width direction of said magnetoresistive element;
• wherein said magnetoresistive element comprises an antiferromagnetic layer, a second magnetic layer on the antiferromagnetic layer, a non-magnetic interlayer on the second magnetic layer, and a first magnetic layer on the non-magnetic interlayer;
• wherein said first magnetic layer includes a specific region at each end thereof in the track width direction;
• the first magnetic film has a thickness at each said specific region that is thinner than that at a central part of said first magnetic layer;
• and
• each said specific region has a width Xe defined by the equation 0.08≦Xe/Twr≦0.2, where Twr denotes the track width of the first magnetic layer.

A magnetoresistive head, comprising:

• an upper shield;
• a lower shield;
• a magnetoresistive element provided between said upper and lower shields;
• and
• a magnetic domain controlling film provided at each end of the magnetoresistive element in a track width direction of said magnetoresistive element;
• wherein said magnetoresistive element comprises an antiferromagnetic layer, a second magnetic layer on the antiferromagnetic layer, a non-magnetic interlayer on the second magnetic layer, and a first magnetic layer on the non-magnetic interlayer;
• said first magnetic layer includes a specific region at each end of the first magnetic layer in the track width direction;
• the saturation magnetization of said specific region is smaller than that at a central part of said first magnetic layer, and
• said specific region has a width Xe defined by the equation 0.08≦Xe/Twr≦0.2, where Twr denotes the track width of the first magnetic layer.