  We report the electrical detection of magnetization dynamics in an
Al/AlOx/Ni80Fe20/Cu tunnel junction, where a Ni80Fe20 ferromagnetic layer is
brought into precession under the ferromagnetic resonance (FMR) conditions. The
dc voltage generated across the junction by the precessing ferromagnet is
enhanced about an order of magnitude compared to the voltage signal observed
when the contacts in this type of multilayered structure are ohmic. We discuss
the relation of this phenomenon to magnetic spin pumping and speculate on other
possible underlying mechanisms responsible for the enhanced electrical signal.
