  We observed unexpected resonant response in [Fe/Cr]_(10) multilayers
epitaxially grown on MgO(100) substrates which exists only when both ac current
and dc magnetic field are simultaneously applied. The magnitude of the
resonances is determined by the multilayer magnetization proving their
intrinsic character. The reduction of interface epitaxy leads to non-linear
dependence of the magnitude of resonances on the alternating current density.
We speculate that the existence of the interface transition zone could
facilitate the subatomic vibrations in thin metallic films and multilayers
grown on bulk insulating substrates.
