A CPP-type magnetoresistive element including a fixed magnetization layer,
a non-magnetic metal layer, and a free magnetization layer that are
stacked, and a diffusion prevention layer is disclosed. The free
magnetization layer includes CoMnAl. The diffusion prevention layer is
provided between the non-magnetic metal layer and the free magnetization
layer so as to prevent Mn included in the free magnetization layer from
diffusing into the non-magnetic metal layer. CoMnAl has a composition
within the area formed by connecting Point A (44, 23, 33), Point B (48,
25, 27), Point C (60, 20, 20), Point D (65, 15, 20), Point E (65, 10,
25), Point F (60, 10, 30), and Point A with straight lines in this order
in a ternary composition diagram where coordinates of the composition are
expressed as (Co content, Mn content, Al content) with each of the Co,
Mn, and Al contents being expressed in atomic percentage.