[en] In three-component superlattices of [(NdMnO3)_n/(SrMnO3)_n/(LaMnO3)_n]_m consisting of nonferroelectric and antiferromagnetic layers, the generation of coherent phonons in the system is investigated by the relaxation process of the superlattice using a pump–probe technique. The coherent phonons are related to MnO₆ octahedra in the layers. While the frequency of the phonons is 49 GHz without regard to the period of each layer, the amplitude of the phonons is influenced by the period of the superlattices. The superlattices have the maximum amplitude of the acoustic phonons at a period of (5, 12) together with strong emergent interfacial effects such as ferromagnetism and ferroelectricity, which are not present in bulk materials. This implies a possible correlation of the lattice structure with interface-induced properties.