Patent ID: 7649719

Claim:
A current perpendicular to plane dual giant magnetoresistive (dual CPP GMR) sensor, comprising: a first pinned layer structure; a second pinned layer structure; a free layer disposed between the first and second pinned layer structures; a first non-magnetic, electrically conductive spacer layer sandwiched between the first pinned layer structure and the free layer; a second non-magnetic, electrically conductive spacer layer sandwiched between the second pinned layer structure and the free layer; and an antiferomagnetic material (AFM layer) in contact with the first pinned layer structure; the first pinned layer structure further comprising: a magnetic AP1 structure that includes a layer of CoFe exchange coupled with the AFM layer; a plurality of Co layers, and at least one spin blocking layer sandwiched between at least two of the Co layers; a magnetic AP2 structure that includes a plurality of CoFe layers and at least one nano-layer sandwiched between at least two of the CoFe layers; and a non-magnetic antiparallel coupling layer sandwiched between the AP1 structure and the AP2 structure.