  Dynamic response of spin accumulation to a time-dependent magnetic field has
been investigated in a ferromagnetic/nonmagnetic bilayer under ferromagnetic
resonance. In this system, magnetization precession driven by a microwave
generates direct-current (dc) and alternate-current (ac) spin accumulation in
the nonmagnetic layer by the spin pumping. The ac spin accumulation is coupled
with the microwave magnetic field through a dynamical Hanle spin precession,
giving rise to rectified spin accumulation comparable with the dc spin
accumulation directly generated by the spin pumping.
