▎ 摘　　要

Effects of electron-phonon interaction oil the optical-phonon spectrum are studied within the lowest order perturbation in a bilayer graphene with potential difference associated with applied electric field. Due to the asymmetry of two layers, symmetric and antisymmetric modes are strongly mixed with each other and two peaks appear in Raman spectra. This behavior can also be controlled by a field due to an extra top gate. When the external field is sufficiently strong and opens up a gap comparable to the phonon energy, the phonons are modified considerably by resonant interband transitions.