A magnetoresistive device includes a magnetization pinned layer, a
magnetization free layer, a nonmagnetic intermediate layer formed between
the magnetization pinned layer and the magnetization free layer, and
electrodes allowing a sense current to flow in a direction substantially
perpendicular to the plane of the stack including the magnetization
pinned layer, the nonmagnetic intermediate layer and the magnetization
free layer. At least one of the magnetization pinned layer and the
magnetization free layer is substantially formed of a binary or ternary
alloy represented by the formula Fe.sub.aCo.sub.bNi.sub.c (where
a+b+c=100 at %, and a.ltoreq.75 at %, b.ltoreq.75 at %, and c.ltoreq.63
at %), or formed of an alloy having a body-centered cubic crystal
structure.