A magnetoresistive film has at least a first magnetic layer, a second magnetic
layer, a nonmagnetic layer, a third magnetic layer, and a fourth magnetic layer
stacked in the order named. In the magnetoresistive film, at least the first magnetic
layer contains Gd and the fourth magnetic layer contains Tb and/or Dy, each of
the first magnetic layer and fourth magnetic layer has an easy axis of magnetization
along a perpendicular direction to a film plane, and the second magnetic layer
and the third magnetic layer have a greater spin polarization than the first magnetic
layer and the fourth magnetic layer. Furthermore, the second and third magnetic
layers are magnetic layers containing at least Co and Co contents thereof are not
less than 20 at. % nor more than 90 at. %.
