A laminating structure includes a first magnetic layer, a second magnetic layer, a first spacer disposed between the first and second magnetic layers and a second spacer disposed on the second magnetic layer.

A laminating structure includes a first magnetic layer, a second magnetic layer, a first spacer disposed between the first and second magnetic layers and a second spacer disposed on the second magnetic layer.

A laminating structure includes a first magnetic layer, a second magnetic layer, a first spacer disposed between the first and second magnetic layers and a second spacer disposed on the second magnetic layer.

A spin transfer oscillator (STO) with a seed/FGL/spacer/SIL/capping configuration is disclosed with a composite seed layer made of Ta and a metal layer having a fcc(111) or hcp(001) texture to enhance perpendicular magnetic anisotropy (PMA) in an overlying (A1/A2).sub.YFeCo laminated field generation layer (FGL). The spin injection layer (SIL) may be laminated with a (A1/A2).sub.XFeCo configuration. The FeCo layer in the SIL is exchanged coupled with the (A1/A2).sub.X laminate (x is 5 to 50) to improve robustness. The (A1/A2).sub.Y laminate (y=5 to 30) in the FGL may be exchange coupled with a high Bs layer to enable easier oscillations. A1 may be one of Co, CoFe, or CoFeR where R is a metal, and A2 is one of Ni, NiCo, or NiFe. The STO is typically formed between a main pole and trailing shield in a write head.

A magnetoresistance effect element includes a first ferromagnetic layer, a second ferromagnetic layer, and a non-magnetic layer positioned between the first ferromagnetic layer and the second ferromagnetic layer, and at least one of the first ferromagnetic layer and the second ferromagnetic layer is a Heusler alloy represented by the following General Formula (1):

Co.sub.2Fe.sub.X(1)

(in Formula (1), X represents one or more elements selected from the group consisting of Mn, Cr, Si, Al, Ga and Ge, and and represent numbers that satisfy 2.3+, <, and 0.5<<1.9).

Methods and apparatus for a sensor having a TMR stack with first and second vortices that are antiferromagnetically coupled together in a synthetic anti-ferromagnet (SAF) arrangement to create a TMR free layer. Due to the opposite behavior of the vortices, and to the coupling which opposes them, relatively strong fields are needed to induce magnetic modifications in the free layer. With this arrangement, the free layer of the stack has relatively wide linear response.