A magnetoresistive element includes a pair of ferromagnetic layers and a non-magnetic
layer arranged between the ferromagnetic layers. At least one of the ferromagnetic
layers has a composition expressed by (MxLy)100-zRz
at the interface with the non-magnetic layer. The non-magnetic layer includes at
least one element selected from the group consisting of B, C, N, O, and P. Here,
M is FeaCobNic, L is at least one element selected
from the group consisting of Pt, Pd, Ir, and Rh, R is an element that has a lower
free energy to form a compound with the element of the non-magnetic layer that
is at least one selected from the group consisting of B, C, N, O, and P than does
any other element included in the composition as M or L, and a, b, c, x, y, and
z satisfy a+b+c=100, a30, x+y=100, 0
