  We theoretically study the ferromagnetic resonance (FMR) modulation in
bilayer systems composed of a superconductor (SC) and a ferromagnetic
insulator. The FMR modulation is determined by the dynamical spin
susceptibility of SCs, which reflects the pairing symmetry. This means that the
pairing symmetry can be detectable by the FMR measurements. We consider the
spin-singlet s-wave, the spin-triplet Chiral p-wave, and the spin-triplet
Helical p-wave SCs and show that they are distinguished by the qualitative
behavior of the FMR frequency shift. The FMR frequency shift is closely related
to the real part of the dynamical spin susceptibility and sensitive to the
interface quality of the bilayer systems. We find that the spin-singlet s-wave
and spin-triplet p-wave SCs can be distinguished by the absence or presence of
a resonance peak of the FMR frequency shift. Furthermore, the spin-triplet
Chiral and Helical p-wave SCs can be distinguished by the angular dependence of
the magnetization direction if the interface is flat.
