  We consider a superconductor in which the density of states at the Fermi
level or the pairing interaction is driven periodically with a frequency larger
than the superconducting gap in the collisionless regime. We show by numerical
and analytical computations that a subset of quasiparticle excitations enter
into resonance and perform synchronous Rabi oscillations leading to cyclic
population inversion with a frequency that depends on the amplitude of the
drive. As a consequence a new "Rabi-Higgs" mode emerges. Turning off the drive
at different times and modulating the strength allows access to all known
dynamical phases of the order parameter: persistent oscillations, oscillations
with damping and overdamped dynamics. We discuss physical realizations of the
drive and methods to detect the dynamics.
