  We propose a new Rashba-free mechanism to realize topological
superconductivity with electron-phonon interaction. In the presence of a
magnetic field, electron-phonon interaction with small momentum transfer is
found to favor spin-triplet Cooper pairing. This process facilitates the
formation of chiral topological superconductivity even when Rashba spin-orbital
coupling is absent. As a proof of concept, we propose an experimentally
feasible heterostructure to systematically study the entangled relationship
among forward-phonon scatterings, Rashba spin-orbital couplings, pairing
symmetries, and superconducting topology. Our theory sheds light on the
important role of electron-phonon coupled materials in the pursuit of
non-Abelian Majorana quasiparticles.
