  We study the magnetization dynamics in a ferromagnet-insulator-superconductor
tunnel junction and the associated buildup of the electrical polarization. We
show that for an open circuit, the induced voltage varies strongly and
nonmonotonically with the precessional frequency, and can be enhanced
significantly by the superconducting correlations. For frequencies much smaller
or much larger than the superconducting gap, the voltage drops to zero, while
when these two energy scales are comparable, the voltage is peaked at a value
determined by the driving frequency. We comment on the potential utilization of
the effect for the low-temperature spatially-resolved spectroscopy of magnetic
dynamics.
