  Current induced spin-orbit torques have been studied in ferromagnetic
nanowires made of 20 nm thick Co/Pd multilayers with perpendicular magnetic
anisotropy. Using Hall voltage and lock-in measurements, it is found that upon
injection of an electric current both in-plane (Slonczewski-like) and
perpendicular (field-like) torques build up in the nanowire. The torque
efficiencies are found to be as large as 1.17 kOe and 5 kOe at 108 A/cm2 for
the in-plane and perpendicular components, respectively, which is surprisingly
comparable to previous studies in ultrathin (~ 1 nm) magnetic bilayers. We show
that this result cannot be explained solely by spin Hall effect induced torque
at the outer interfaces, indicating a probable contribution of the bulk of the
Co/Pd multilayer.
