Dependence of the Exchange Bias and Coercivity of [Pd/Ferromagnet]$_N$/FeMn Multilayers on the Stack Number$N$

The dependencies of the stack number
$N$
on perpendicular exchange-biasing
$(H_ ex)$
and coercivity
$H_ c$
) in [Pd/Co]
$_N$
and [Pd/Co (or CoFe)]
$_N$
/FeMn multilayers were investigated. With the help of the careful designs of layer structures, a series of samples whose surface anisotropies have the linear function
$N$
was prepared with constant bulk anisotropies. From the experimental data obtained, it was found that
$H_ ex$
does not depend on the surface anisotropy, while
$H_ c$
shows a strong dependence. Therefore, it is possible to tailor wide ranges of
$H_ c$
(300–600 Oe) without varying
$H_ ex$
(
$sim!hbox200$
Oe) through the single control parameter stack number
$N$
.