  We investigate the electric response of chiral phonons on the low-buckled
group-IVA monolayers by performing first-principles calculations. The vertical
electric field breaks the degeneracy of phonon modes at high-symmetry $\pm K$
points of the phonon Brillouin zone, and the size of the phononic gap is
proportional to the strength of the electric field. The gapped phonon modes at
$\pm K$ possess chiralities with considerable phonon circular polarizations and
discrete phonon pseudoangular momenta. The chiralities of phonons are robust
against the variation of the field strength, but reversed by changing the field
direction. Electric control of chiral phonons adds a new dimension to the study
of chiral phonons, which has potential use in the design of phononic and valley
devices.
